Property Estimate API

Instant expected sale price range, council valuation, sales history and rental estimate for any NZ address. Built to be fed straight from the Google Places API. Requires an API key.

Base URL

https://estimate.remark.nz

All endpoints are GET, return JSON unless noted, and allow cross-origin requests from any page (Access-Control-Allow-Origin: *).

Authentication

Every endpoint except this page and /health needs an API key. You will have been given one; if not, email oj@remark.nz. Send it in any one of these ways:

A missing or wrong key returns 401 {"error":"unauthorised"}. Keys are per person or per app, so keep yours out of public repos and client-side code where possible; if it leaks, ask for it to be rotated. If you must call from a browser, proxy through your own backend or accept that the key is visible.

Calls are logged (timestamp, key label, address queried, result, status, latency, caller IP and country) for support and fair-use monitoring. The key itself is never stored.

Endpoints

URL-encode the address if your client does not do it for you (%20 for spaces, %2F for the slash in 3/15 Frankton Road). A suburb or town after the street helps disambiguate; a comma is optional.

Feeding it from Google Places

Two ways, pick whichever your code already has in hand.

1. Pass formatted_address as-is

https://estimate.remark.nz/estimate?address=10 Hassing Place, Cromwell 9310, New Zealand

The postcode and , New Zealand are stripped automatically before matching.

2. Pass the address_components types as parameters

https://estimate.remark.nz/estimate?subpremise=3&street_number=15&route=Frankton Road&sublocality=Queenstown&locality=Queenstown

// JavaScript: from a Places Autocomplete place object
const get = t => (place.address_components.find(c => c.types.includes(t)) || {}).long_name || '';
const params = new URLSearchParams({
  subpremise: get('subpremise'), street_number: get('street_number'), route: get('route'),
  sublocality: get('sublocality') || get('sublocality_level_1') || get('neighborhood'),
  locality: get('locality'),
});
const data = await (await fetch('https://estimate.remark.nz/estimate?' + params, { headers: { Authorization: 'Bearer YOUR_KEY' } })).json();

If both address and components are sent, address wins. Restrict Places Autocomplete to componentRestrictions: { country: 'nz' } and types: ['address'] for best results.

Examples

curl

curl -H "Authorization: Bearer YOUR_KEY" "https://estimate.remark.nz/estimate?address=10%20Hassing%20Place%2C%20Cromwell&format=text"
curl -H "Authorization: Bearer YOUR_KEY" "https://estimate.remark.nz/estimate?address=10%20Hassing%20Place%2C%20Cromwell" | jq .estimate

PowerShell

$h = @{ Authorization = "Bearer YOUR_KEY" }
$r = Invoke-RestMethod "https://estimate.remark.nz/estimate?address=10 Hassing Place, Cromwell" -Headers $h
$r.estimate            # low / mid / high / date
$r.council_valuation.capital
Invoke-RestMethod "https://estimate.remark.nz/estimate?address=10 Hassing Place, Cromwell&format=text" -Headers $h

Python

import requests
H = {"Authorization": "Bearer YOUR_KEY"}
r = requests.get("https://estimate.remark.nz/estimate", params={"address": "10 Hassing Place, Cromwell"}, headers=H).json()
if "error" in r:
    print(r["error"])
else:
    e = r["estimate"]
    print(r["matched_address"], e["low"], e["mid"], e["high"], e["date"])

JavaScript (browser or Node)

const res = await fetch("https://estimate.remark.nz/estimate?address=" + encodeURIComponent("10 Hassing Place, Cromwell"), {
  headers: { Authorization: "Bearer YOUR_KEY" },
});
const data = await res.json();
if (data.error) console.log(data.error);
else console.log(data.matched_address, data.estimate.low, data.estimate.high);

Google Sheets

=IMPORTDATA("https://estimate.remark.nz/estimate?address="&ENCODEURL(A2)&"&format=text&key=YOUR_KEY")

Sheets caches IMPORTDATA results for a while; the text format keeps the result to one cell.

Response shape

{
  "query": "10 Hassing Place, Cromwell",
  "matched_address": "10 Hassing Place, Cromwell",     // always check this
  "property_id": "10a2cfb4-3f55-426b-8e7b-a4e268b01121",
  "lat": -45.0412, "lng": 169.1841,

  "estimate": {                       // null if no estimate exists for the property
    "low": 810000, "mid": 865000, "high": 915000,
    "date": "2026-09-03",             // when the estimate was last revised
    "display": "$810K – $915K",
    "model": "v3 (2025-01-22)"
  },
  "rental_estimate": { "low_per_week": 880, "high_per_week": 1480, "date": "2026-06-02", "gross_yield": "7.1%" },
  "council_valuation": {
    "capital": 830000, "land": 480000, "improvements": 350000, "date": "2025-09-01",
    "history": [ { "date": "2025-09-01", "capital": 830000, … }, { "date": "2022-10-01", … } ]
  },
  "last_sale": { "price": 383000, "date": "2014-08-13", "type": "S11", "council_confirmed": true },
  "sales": [ …every recorded sale, newest first… ],
  "property": {
    "bedrooms": 3, "bathrooms": 2, "car_spaces": 1,
    "floor_area_m2": 185, "land_area_m2": 644, "decade_built": "1970",
    "ownership": "Freehold", "land_use": "house",
    "legal_description": "LOT 5 DP 17109", "title": "OT11C/1270", "valuation_ref": "28506/19100",
    "suburb": "Cromwell", "city": "Cromwell"
  },
  "listing": {                        // only present while the property is on the market
    "headline": "Space, Flexibility and Greenway Living",
    "display_price": "Deadline sale by 24 Sept",
    "agency": "PGG Wrightson",
    "trademe_ids": ["6112545398"],
    "cover_image": "https://…"
  },
  "trademe_url": "https://www.trademe.co.nz/a/property/residential/sale/listing/6112545398",
  "candidates": [ …other address matches, if the top pick looks wrong… ],
  "fetched_at": "2026-09-13T01:02:03.000Z"
}

All money values are whole NZ dollars. Areas are square metres. Dates are YYYY-MM-DD.

Errors

Error bodies are JSON: {"query": "…", "error": "…", "status": 404}. Success bodies never contain an error key, so if (data.error) is a safe check.

Good to know

• Check matched_address. Address matching is fuzzy and can drop a unit number (3/15 Frankton Road may come back as 15 Frankton Road) or pick a same-named street in another town if you omit the suburb.
• Freshness. The estimate refreshes about monthly (see estimate.date). Each successful lookup is cached for 6 hours; &nocache=1 bypasses that. Response header x-cache says HIT or MISS.
• Speed. Roughly 300–500 ms uncached, about 10 ms cached.
• Accuracy. This is an automated model estimate, not a valuation. For a bank-grade figure use a registered valuer or a full property report.
• Fair use. Personal and small-batch use only. There is no rate limit, so please do not hammer it.

Questions? Contact oj@remark.nz for support.