Build/Property
⌂Property Namespace

Build a property tools business.
Stamp duty to rent-vs-buy.

Stamp duty in 14 countries, property tax in 39, full loan amortization schedules, DTI-based mortgage affordability, rent-vs-buy modeling, and rental yield — six endpoints that are pure computation or static owned datasets, with zero third-party calls. These are estimate tools for screening and comparison, not financial advice, and the copy below says so honestly.

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The opportunity

Real numbers. No projections inflated to impress.

14
Countries with stamp duty tier data
Owned, hand-curated dataset — covers the biggest property markets
0
Third-party API calls at runtime
Pure computation or owned static data — no upstream rate limits
20
Endpoints: tax, mortgage, valuation, investment analysis, neighborhood scoring, and more
Full real-estate decision toolkit, from first-home grants to commercial lease-vs-buy
$19–49
Monthly APlicious cost for most indie/B2B embeds
Starter/Growth plan covers typical calculator-widget volume

3 businesses you can build this month

Each one is a complete business, not a demo. Revenue estimates are conservative and show the math. These are illustrative estimates based on stated assumptions, not guarantees of revenue. All three are positioned as estimate and screening tools — not licensed financial advice.

Real estate agency sites send buyers to generic third-party calculators that don't match local stamp duty or tax rules. KeyMath is a drop-in widget showing monthly payment, amortization schedule, and total cost of ownership for a listing — branded to the agency's site. Sell as a B2B embed to brokerages and listing portals.

Pricing Model
$39/month per agency site (B2B SaaS embed)
Build Time
2–3 weeks solo
Revenue Target
$1,950/month
Gross Margin
97.5% gross margin
Revenue Math

50 small/mid brokerages × $39. Conservative — most regional brokerages currently embed a free, unbranded calculator from a bank's site and would pay for one that keeps buyers on their own page.

Endpoints Used
/property/amortization
/property/stamp-duty
APlicious Cost
$49 (Growth plan — 50 sites × 10 × 30 = 15,000 calls/mo)
~10 calls/day per active agency site

All 20 endpoints

Pure computation or owned static datasets. No third-party calls, no data licensing, no rate limits from upstream.

Starter code — KeyMath

Two API calls in parallel. Stamp duty plus a full amortization summary for one listing.

keymath.ts
// KeyMath — Mortgage Calculator Widget
// Built with APlicious Property namespace
// Replace YOUR_API_KEY with your key from aplicious.com/dashboard

const API_BASE = "https://aplicious.com/api/v1";
const API_KEY = "YOUR_API_KEY";

async function getPurchaseSnapshot(
  country: string,
  propertyValue: number,
  loanAmount: number,
  annualRate: number,
  years: number
) {
  const [stampDuty, amortization] = await Promise.all([
    fetch(
      `${API_BASE}/property/stamp-duty?country=${country}&property_value=${propertyValue}`,
      { headers: { "x-api-key": API_KEY } }
    ).then((r) => r.json()),

    fetch(
      `${API_BASE}/property/amortization?loan_amount=${loanAmount}&annual_rate=${annualRate}&years=${years}`,
      { headers: { "x-api-key": API_KEY } }
    ).then((r) => r.json()),
  ]);

  return {
    stampDuty: stampDuty.data.stamp_duty,
    effectiveRatePct: stampDuty.data.effective_rate_pct,
    monthlyPayment: amortization.data.monthly_payment,
    totalInterest: amortization.data.total_interest,
  };
}

// Example output:
// {
//   stampDuty: 21000,
//   effectiveRatePct: 4.2,
//   monthlyPayment: 2398.2,
//   totalInterest: 311552.0
// }

Revenue calculator

Slide to see how the numbers stack up. The API cost is real — pulled from our pricing page.

50
5500
Gross MRR
$1,950
at $39/customer
APlicious Plan
Growth ($49)
15,000 calls/mo
API Cost
$49
per month
Net MRR
$1,901
97.5% margin

Model: KeyMath — $39/month per B2B agency site customer, ~10 API calls/customer/day. API plan auto-selects based on call volume. These are revenue projections, not guarantees. Figures are estimates for screening and comparison, not financial advice — build quality and distribution determine actual results.

⌂

Start building today

Free plan. 10,000 API calls per month. No credit card required. The Property namespace is live and ready.

Questions? Talk to us