Source: https://guthlabs.ai/docs/instrument-workflows/mortgage-suite/

instrument chain / verified-workflow-definition

# Mortgage Suite

Buy, amortize, optimize, refinance.

Status: **observed**Lifecycle: **verified-workflow-definition**

## Goal

Buy, amortize, optimize, refinance.

## Instrument chain

- 01

**[Closing Costs & Cash-to-Close Estimator](<https://guthlabs.ai/docs/instruments/closing-costs-cash-to-close-estimator/>)**

day 0

VERIFIED

- 02

**[Loan/Mortgage Payment](<https://guthlabs.ai/docs/instruments/loan-mortgage-payment/>)**

payment

VERIFIED

- 03

**[Amortization Schedule](<https://guthlabs.ai/docs/instruments/amortization-schedule/>)**

schedule

VERIFIED

- 04

**[PMI / LTV Estimator](<https://guthlabs.ai/docs/instruments/pmi-ltv-estimator/>)**

PMI drop-off

VERIFIED

- 05

**[Extra-Payment Payoff Impact](<https://guthlabs.ai/docs/instruments/extra-payment-payoff-impact/>)**

optimization

VERIFIED

- 06

**[Refinance Break-Even](<https://guthlabs.ai/docs/instruments/refinance-break-even/>)**

refi decision

VERIFIED

- 07

**[APR vs APY Converter](<https://guthlabs.ai/docs/instruments/apr-vs-apy-converter/>)**

rate literacy

VERIFIED

- 08

**[Debt-to-Income Ratio Calculator](<https://guthlabs.ai/docs/instruments/debt-to-income-ratio-calculator/>)**

qualification

VERIFIED

- 09

**[Rent vs Buy (Home) Comparator](<https://guthlabs.ai/docs/instruments/rent-vs-buy-home-comparator/>)**

the big question

VERIFIED

## Handoffs and cross-checks

Loan amount → payment → schedule → LTV timeline → extra-payment and refi scenarios.

## PointGuard stance

The amortization table is the source of truth: payment×n − principal must equal total interest to the cent (the t2-044/t3-008 failure modes).

## Sources and evidence

These pointers bind the page to evidence. They do not grant authority or collapse verification into deployment.

- `INSTRUMENT_COMBOS.json`

- `VERIFIED_LEDGER.json`