API Documentation

Access FairLot's mobile home park lot rent database programmatically. Search parks, retrieve rent data, and build integrations with our REST API.

Overview

The FairLot API provides read-only access to mobile home park data across multiple US states. All responses are JSON. API access requires the Founding Member plan ($33/mo billed annually at $396/yr, or $49/mo billed monthly).

The API covers 600+ parks across Vermont and Nevada, with verified lot rent data for 500+ parks.

Quickstart

Get up and running with the FairLot API in three steps.

Subscribe to the Founding Member plan Sign up at fairlot.org/#pricing and subscribe to the Founding Member plan ($33/mo billed annually at $396/yr, or $49/mo billed monthly).
Generate an API key From your dashboard, go to Settings > API Keys and create a new key. Your key will start with fl_live_.
Make your first request Try fetching parks with rent data:

curl "https://fairlot.org/api/v1/parks?state=VT&has_rent=true&per_page=5" \ -H "Authorization: Bearer fl_live_your_key_here"

import requests resp = requests.get( "https://fairlot.org/api/v1/parks", headers={"Authorization": "Bearer fl_live_your_key_here"}, params={"state": "VT", "has_rent": "true", "per_page": 5} ) data = resp.json() print(f"Found {data['total']} parks") for park in data["parks"]: print(f" {park['name']}: ${park['latest_lot_rent']}/mo")

const resp = await fetch( "https://fairlot.org/api/v1/parks?state=VT&has_rent=true&per_page=5", { headers: { "Authorization": "Bearer fl_live_your_key_here" } } ); const data = await resp.json(); console.log(`Found ${data.total} parks`); data.parks.forEach(p => console.log(` ${p.name}: $${p.latest_lot_rent}/mo`) );

Tip: Start with the List Parks endpoint to browse available data, then use Get Park Detail for full rent history on individual parks.

Base URL

https://fairlot.org/api/v1

All endpoints are under the /api/v1/ prefix. For example, the parks list endpoint is:

GET https://fairlot.org/api/v1/parks

Versioning: The current API version is v1. The legacy /api/ prefix (without a version) still works and behaves identically to /api/v1/, but new integrations should use the versioned URL so they are not affected by future changes.

OpenAPI Specification

A machine-readable OpenAPI 3.1 spec is available for client code generation and tooling integration.

curl "https://fairlot.org/api/v1/openapi.json" | python -m json.tool

You can use this spec with tools like OpenAPI Generator, openapi-ts, or import it directly into Postman or Insomnia.

Authentication

FairLot supports two authentication methods:

1. API Keys (Recommended)

Generate an API key from your dashboard. Include it as a Bearer token:

curl https://fairlot.org/api/v1/parks?state=VT&has_rent=true \
  -H "Authorization: Bearer fl_live_your_key_here"

2. Session Cookie

For browser-based access, sign in at fairlot.org and the session cookie authenticates automatically.

Plan-Based Access

API responses vary based on your subscription plan. Unauthenticated requests receive limited data with certain fields stripped.

Capability	Free (Resident)	Founding Member ($33/mo or $49/mo)
Park list (basic fields)	Yes	Yes (full)
Lot rent data	Teaser only (3 per page)	Full (all data points)
Owner name, phone, address	No	Yes
Park detail endpoint	No (401)	Yes
Full rent history	No	Yes
CSV export	No	Yes (watermarked)
API access	No	Yes
Max results per page	50	200
Daily view limit	N/A	150 parks/day

Free tier teaser: Unauthenticated requests to /api/v1/parks will show rent data for up to 3 parks per page, but only for a limited number of parks per page. All other rent-related fields are stripped. To access full data, subscribe at fairlot.org/landing.html#pricing.

Rate Limiting

All API requests are rate-limited using a sliding window algorithm. Rate limit status is returned in response headers on every request.

Header	Description
X-RateLimit-Limit	Maximum requests allowed in the current window
X-RateLimit-Remaining	Requests remaining in the current window
X-RateLimit-Reset	Seconds until the rate limit window resets
Retry-After	Seconds to wait before retrying (only on 429 responses)

Rate Limit Tiers

Tier	Limit	Window	Applies To
Public (unauthenticated)	60 requests	60 seconds	IP-based, non-search requests
Search (unauthenticated)	30 requests	60 seconds	IP-based, requests with search terms
Authenticated	120 requests	60 seconds	User-based, all authenticated requests

429 Rate Limited Response

{
  "detail": "Too many requests. Please slow down."
}

Pagination

List endpoints return paginated results. Use the page and per_page query parameters to navigate through results.

Parameter	Type	Default	Description
page	integer	1	Page number (1-indexed)
per_page	integer	50	Results per page (max 50 for free, 200 for Founding Member)

The response includes total, page, and per_page fields so you can calculate total pages:

// total_pages = ceil(total / per_page)
{
  "total": 238,
  "page": 1,
  "per_page": 50,
  "parks": [...]
}

Sorting

Use the sort and dir parameters to control result ordering on list endpoints.

Sort Column	Description
name	Park name (default)
county	County name
metro_area	Metro area name
lot_count	Number of lots
latest_lot_rent	Most recent lot rent amount
owner_name	Park owner name
fetched_at	Date the record was last updated

Direction: dir=asc (default) or dir=desc. The order parameter is accepted as an alias for dir.

Error Handling

The API returns standard HTTP status codes. Error responses include a JSON body with a detail field.

Status	Meaning	Example
`200`	Success	Request completed
`401`	Unauthorized	Missing or invalid session cookie
`403`	Forbidden	Plan upgrade required for this endpoint
`404`	Not Found	Park ID does not exist
`429`	Too Many Requests	Rate limit exceeded (check `Retry-After` header)

Error response format

{
  "detail": "Authentication required"
}

List Parks

GET /api/v1/parks

Search and filter mobile home parks across all states. Returns a paginated list of parks with optional rent data. This is the primary endpoint for browsing the FairLot database.

Query Parameters

Parameter	Type	Default	Description
state	string	none	Filter by state abbreviation (e.g., `VT`, `NV`)
county	string	none	Filter by county name
metro_area	string	none	Filter by metro area name
min_lots	integer	none	Minimum lot count. Alias: `lot_count_min`
max_lots	integer	none	Maximum lot count. Alias: `lot_count_max`
has_rent	boolean	none	When `true`, only return parks that have lot rent data
q	string	none	Full-text search across park name. Aliases: `name`, `search`
owner_name	string	none	Filter by park owner name
status	string	Approved	Filter by registration status
sort	string	name	Sort column (see Sorting)
dir	string	asc	Sort direction: `asc` or `desc`. Alias: `order`
page	integer	1	Page number (1-indexed)
per_page	integer	50	Results per page (max 50 free, 200 Founding Member)

Example: Vermont parks with rent data

curl "https://fairlot.org/api/v1/parks?state=VT&has_rent=true&per_page=3" \
  -H "Authorization: Bearer fl_live_your_key_here"

import requests

resp = requests.get(
    "https://fairlot.org/api/v1/parks",
    headers={"Authorization": "Bearer fl_live_your_key_here"},
    params={"state": "VT", "has_rent": "true", "per_page": 3}
)
data = resp.json()
print(data["total"], "parks found")

const resp = await fetch(
  "https://fairlot.org/api/v1/parks?state=VT&has_rent=true&per_page=3",
  { headers: { "Authorization": "Bearer fl_live_your_key_here" } }
);
const data = await resp.json();
console.log(data.total, "parks found");

Response

{
  "total": 216,
  "page": 1,
  "per_page": 3,
  "parks": [
    {
      "id": "vt-chittenden-birchwood",
      "name": "Birchwood Mobile Home Park",
      "county": "Chittenden",
      "city": "Essex",
      "address": "123 Birchwood Ln",
      "state": "VT",
      "zip": "05452",
      "lot_count": 84,
      "owner_name": "Green Mountain Properties LLC",
      "status": "Approved",
      "phone": "(802) 555-0142",
      "metro_area": "Burlington-South Burlington",
      "park_size_category": "Medium (50-99)",
      "source": "vt_registry",
      "fetched_at": "2025-11-15T14:30:00",
      "latest_lot_rent": 435.0,
      "latest_rent_source": "verified",
      "latest_rent_collected_at": "2024-07-01T00:00:00",
      "latitude": 44.4918,
      "longitude": -73.1148,
      "age_restriction": null,
      "estimated_occupancy": null
    },
    // ... more parks
  ]
}

Example: Large parks sorted by rent (descending)

curl "https://fairlot.org/api/v1/parks?state=NV&min_lots=100&sort=latest_lot_rent&dir=desc" \
  -H "Authorization: Bearer fl_live_your_key_here"

Example: Search by park name

curl "https://fairlot.org/api/v1/parks?q=maple&state=VT" \
  -H "Authorization: Bearer fl_live_your_key_here"

Get Park Detail

GET /api/v1/parks/{park_id}

Retrieve detailed information for a single park, including its full rent history. Requires authentication (Founding Member plan). Full rent history is included with the Founding Member plan.

Path Parameters

Parameter	Type		Description
park_id	string	required	The unique park identifier (from the list endpoint)

Example

curl "https://fairlot.org/api/v1/parks/vt-chittenden-birchwood" \
  -H "Authorization: Bearer fl_live_your_key_here"

import requests

resp = requests.get(
    "https://fairlot.org/api/v1/parks/vt-chittenden-birchwood",
    headers={"Authorization": "Bearer fl_live_your_key_here"}
)
park = resp.json()
print(park["name"], "-", len(park["lot_rents"]), "rent records")

const resp = await fetch(
  "https://fairlot.org/api/v1/parks/vt-chittenden-birchwood",
  { headers: { "Authorization": "Bearer fl_live_your_key_here" } }
);
const park = await resp.json();
console.log(park.name, "-", park.lot_rents.length, "rent records");

Response

{
  "id": "vt-chittenden-birchwood",
  "name": "Birchwood Mobile Home Park",
  "county": "Chittenden",
  "city": "Essex",
  "address": "123 Birchwood Ln",
  "state": "VT",
  "zip": "05452",
  "lot_count": 84,
  "owner_name": "Green Mountain Properties LLC",
  "status": "Approved",
  "phone": "(802) 555-0142",
  "metro_area": "Burlington-South Burlington",
  "park_size_category": "Medium (50-99)",
  "source": "vt_registry",
  "fetched_at": "2025-11-15T14:30:00",
  "latitude": 44.4918,
  "longitude": -73.1148,
  "owner_address": "456 Main St, Burlington, VT 05401",
  "age_restriction": null,
  "estimated_occupancy": null,
  "latest_lot_rent": 435.0,
  "lot_rents": [
    {
      "lot_rent_monthly": 435.0,
      "lot_rent_min": 410.0,
      "lot_rent_max": 460.0,
      "lot_rent_double_wide": 510.0,
      "source": "verified",
      "confidence": "high",
      "collected_at": "2024-07-01T00:00:00",
      "notes": null
    },
    {
      "lot_rent_monthly": 410.0,
      "lot_rent_min": 390.0,
      "lot_rent_max": 430.0,
      "lot_rent_double_wide": 480.0,
      "source": "verified",
      "confidence": "high",
      "collected_at": "2023-07-01T00:00:00",
      "notes": null
    }
  ],
  "upgrade_hint": null
}

Founding Member plan: The lot_rents array contains the full rent history for the park. The upgrade_hint field will be null for Founding Member subscribers.

401 Unauthorized

{
  "detail": "Authentication required"
}

404 Not Found

{
  "detail": "Park not found"
}

Aggregate Statistics

GET /api/v1/stats

Returns aggregate statistics across all parks, broken down by state, county, metro area, and park size category. Includes rent stats (median, average, min, max) per grouping. This endpoint is public but rate-limited.

Example

curl "https://fairlot.org/api/v1/stats"

Response (abbreviated)

{
  "total_parks": 613,
  "parks_with_rent_data": 504,
  "rent_snapshot": {
    "count": 504,
    "median": 425.0,
    "avg": 468.32,
    "min": 125.0,
    "max": 1850.0
  },
  "by_state": [
    {
      "state": "NV",
      "park_count": 375,
      "parks_with_rent": 288
    },
    {
      "state": "VT",
      "park_count": 238,
      "parks_with_rent": 216
    }
  ],
  "by_county": [
    {
      "county": "Chittenden",
      "state": "VT",
      "park_count": 24,
      "rent": {
        "count": 19,
        "median": 445.0,
        "avg": 452.38,
        "min": 320.0,
        "max": 610.0
      }
    }
    // ... more counties
  ],
  "by_metro": [
    {
      "metro_area": "Burlington-South Burlington",
      "park_count": 28,
      "rent": {
        "count": 22,
        "median": 440.0,
        "avg": 448.5,
        "min": 310.0,
        "max": 610.0
      }
    }
    // ... more metros
  ],
  "by_size_category": [
    {
      "park_size_category": "Small (1-49)",
      "park_count": 1842
    },
    {
      "park_size_category": "Medium (50-99)",
      "park_count": 614
    },
    {
      "park_size_category": "Large (100-249)",
      "park_count": 423
    },
    {
      "park_size_category": "Very Large (250+)",
      "park_count": 98
    }
  ]
}

Privacy gating: Counties and metros with fewer than 3 rent data points will have their rent stats suppressed (only count will be returned) to prevent re-identification of individual submitters.

Parks GeoJSON

GET /api/v1/parks-geo

Returns all approved parks that have coordinates, optimized for map rendering. This is a lightweight endpoint designed for plotting markers on a map.

Example

curl "https://fairlot.org/api/v1/parks-geo" \
  -H "Authorization: Bearer fl_live_your_key_here"

Response (abbreviated)

{
  "parks": [
    {
      "id": "vt-chittenden-birchwood",
      "name": "Birchwood Mobile Home Park",
      "latitude": 44.4918,
      "longitude": -73.1148,
      "lot_count": 84,
      "county": "Chittenden",
      "state": "VT",
      "owner_name": "Green Mountain Properties LLC",
      "latest_lot_rent": 435.0
    }
    // ... more parks
  ]
}

Field gating: Unauthenticated users will see owner_name as null. The latest_lot_rent field is visible without auth only for a limited number of parks per page as a teaser.

CSV Export

GET /api/v1/export/parks

Export park data as a CSV file. Requires Founding Member plan. The CSV includes watermark rows containing the authenticated user's email to prevent unauthorized redistribution.

Accepts the same filter parameters as the List Parks endpoint (state, county, has_rent, etc.).

Example

curl "https://fairlot.org/api/v1/export/parks?state=VT&has_rent=true" \
  -H "Authorization: Bearer fl_live_your_key_here" \
  -o parks.csv

import requests

resp = requests.get(
    "https://fairlot.org/api/v1/export/parks",
    headers={"Authorization": "Bearer fl_live_your_key_here"},
    params={"state": "VT", "has_rent": "true"}
)
with open("parks.csv", "wb") as f:
    f.write(resp.content)
print("Saved", len(resp.content), "bytes")

const resp = await fetch(
  "https://fairlot.org/api/v1/export/parks?state=VT&has_rent=true",
  { headers: { "Authorization": "Bearer fl_live_your_key_here" } }
);
const blob = await resp.blob();
// Save or process the CSV blob

Returns a text/csv response with columns including Park ID, Name, County, Address, City, State, Zip, Lot Count, Owner, Phone, Metro Area, Size Category, Lot Rent (Monthly), Rent Source, Rent Collected At, Latitude, and Longitude.

List States

GET /api/v1/states

Returns a list of all states in the database with park counts and the number of parks that have rent data. This endpoint is public and does not require authentication.

Example

curl "https://fairlot.org/api/v1/states"

Response

[
  {
    "state": "FL",
    "park_count": 1811,
    "parks_with_rent": 18
  },
  {
    "state": "CO",
    "park_count": 762,
    "parks_with_rent": 0
  },
  {
    "state": "NV",
    "park_count": 375,
    "parks_with_rent": 288
  },
  {
    "state": "VT",
    "park_count": 238,
    "parks_with_rent": 216
  }
]

Response Schemas

ParkListItemResponse

Each park in the /api/v1/parks response contains these fields:

Field	Type	Description
id	string	Unique park identifier
name	string	Park name
county	string?	County name
city	string?	City name
address	string?	Street address (gated)
state	string?	Two-letter state code
zip	string?	ZIP code (gated)
lot_count	integer?	Number of lots in the park
owner_name	string?	Park owner name (gated)
status	string?	Registration status (e.g., "Approved")
phone	string?	Park phone number (gated)
metro_area	string?	Metro/MSA area name
park_size_category	string?	Size bucket (gated)
source	string?	Data source identifier (gated)
fetched_at	string?	ISO 8601 timestamp of last data pull (gated)
latest_lot_rent	float?	Most recent monthly lot rent (gated)
latest_rent_source	string?	Source of the rent data (gated)
latest_rent_collected_at	string?	When rent was collected (gated)
latitude	float?	GPS latitude
longitude	float?	GPS longitude
age_restriction	string?	Age restriction type (e.g., "55+")
estimated_occupancy	float?	Estimated occupancy rate (0-1)

LotRentResponse

Each entry in the lot_rents array on park detail:

Field	Type	Description
lot_rent_monthly	float	Monthly lot rent amount
lot_rent_min	float?	Minimum lot rent in the park
lot_rent_max	float?	Maximum lot rent in the park
lot_rent_double_wide	float?	Lot rent for double-wide homes
source	string?	Data source identifier
confidence	string?	Confidence level: "high", "medium", or "low"
collected_at	string?	ISO 8601 timestamp of data collection
notes	string?	Additional notes about this data point

RentStatsResponse

Aggregate rent stats returned within the /api/v1/stats response:

Field	Type	Description
count	integer	Number of rent data points in this group
median	float?	Median monthly lot rent
avg	float?	Average monthly lot rent
min	float?	Lowest lot rent in the group
max	float?	Highest lot rent in the group

Field Gating

The following fields are set to null for unauthenticated (free tier) users on the /api/v1/parks endpoint:

phone
owner_name
address
zip
source
fetched_at
park_size_category
latest_lot_rent
latest_rent_source
latest_rent_collected_at

Exception: A limited number of parks per page show rent fields (latest_lot_rent, latest_rent_source, latest_rent_collected_at) as a teaser for unauthenticated users.

Support

For API questions, integration help, or to request a dedicated API key, contact us at [email protected].

If you need higher rate limits or custom data exports for enterprise use, let us know your requirements and we will work with you on a solution.