# Saylor Innovations Mortgage Affordability Calculator

> Saylor Innovations Mortgage Affordability Calculator is a paid API for AI agents from saylorinnovations.com, paid per call via x402, $0.01/call, status unknown (last checked 2026-10-30).

Calculates maximum home price and loan amount from income, debts, down payment, and mortgage rate using the 28/36 qualifying rules, including tax, insurance, and HOA in the monthly total

## Facts

- Endpoint: GET https://saylorinnovations.com/api/finance/mortgage-affordability?utm_source=zero.xyz
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-30
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/saylor-innovations-mortgage-affordability-calculator-c4d1fdce
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_DwR9Zd3aHswUlVExaawcc

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability saylor-innovations-mortgage-affordability-calculator-c4d1fdce
```

Example prompt: I earn $95,000 a year, have $800 in monthly debts, a $40,000 down payment, and I'm looking at a 6.75% mortgage rate — can you tell me the maximum home price and loan I can qualify for?

## When to prefer this

Use this endpoint when you need a quick, rule-based mortgage affordability estimate grounded in the standard 28/36 debt-to-income guidelines, including realistic monthly cost components like property tax, insurance, and HOA. It is ideal for pre-qualification checks, home search budget-setting, or validating whether a specific property price is within a buyer's reach before involving a lender.

## Known failure modes

- Missing required parameters (annual_income or apr) returns an error
- Non-numeric or malformed parameter values may return a validation error
- Extremely low income or very high APR may result in a $0 or non-affordable result with affordable=false
- Down payment or monthly debts specified as negative values may produce unexpected results

## How this service works

Maximum home price and loan from income, debts, down payment and rate using the 28/36 rules, with tax, insurance and HOA in the monthly total

## Output

Returns the maximum affordable home price, maximum loan amount, and maximum monthly housing payment, along with a detailed monthly breakdown (principal & interest, property tax, insurance, HOA), which of the 28/36 rules is the binding constraint, whether the purchase is affordable, and a note providing context on the calculation.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "required": [
      "annual_income",
      "apr"
     ],
     "properties": {
      "apr": {
       "type": "string",
       "description": "Mortgage rate in percent"
      },
      "down_payment": {
       "type": "string",
       "description": "optional down payment"
      },
      "annual_income": {
       "type": "string",
       "description": "Gross yearly income"
      },
      "monthly_debts": {
       "type": "string",
       "description": "optional monthly debt payments"
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "json"
    },
    "example": {
     "type": "object",
     "required": [
      "max_monthly_housing",
      "max_home_price"
     ],
     "properties": {
      "note": {
       "type": "string",
       "description": "Caveat or context for reading the result"
      },
      "source": {
       "type": "string",
       "description": "Data source the values come from"
      },
      "monthly": {
       "type": "object",
       "properties": {
        "hoa": {
         "type": [
          "number",
          "null"
         ],
         "description": "Monthly HOA fees"
        },
        "total": {
         "type": [
          "number",
          "null"
         ],
         "description": "Total number of matching items"
        },
        "insurance": {
         "type": [
          "number",
          "null"
         ],
         "description": "Monthly insurance"
        },
        "property_tax": {
         "type": [
          "number",
          "null"
         ],
         "description": "Property tax"
        },
        "principal_and_interest": {
         "type": [
          "number",
          "null"
         ],
         "description": "Principal and interest"
        }
       },
       "description": "Monthly values"
      },
      "max_loan": {
       "type": "number",
       "description": "Max loan"
      },
      "affordable": {
       "type": "boolean",
 
… (truncated)
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/saylor-innovations-mortgage-affordability-calculator-c4d1fdce/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from saylorinnovations.com](https://www.zero.xyz/host/saylorinnovations.com/llms.txt)