Mortgage Planning
Limitations of Mortgage Affordability Simulations
This guide explains what the tool models, what it does not, why lender outputs can differ, why probability is not a prediction, and how to use results safely without over-trusting a single run.
Published: January 1, 2026 · Updated: January 1, 2026 · By FinToolSuite Editorial
Open the stress tester
Run scenarios with clear assumptions and note what the model does and does not include.
Disclaimer
- Educational only. No guarantees. Encourage professional guidance without providing advice.
- Examples are illustrative.
What the tool models
It models rate, income, and cost shocks within your assumptions to produce DTI distributions, recommended safe loan, and model default probability.
What it does not model
It does not include every local lending rule, exact payment schedules, or personal credit factors. Real outcomes can differ.
Why lenders can differ
Lenders use their own criteria, underwriting models, and documentation checks. This tool is separate and educational.
Why probability isn’t prediction
The model default probability depends on your inputs and randomness; it is not a forecast or guarantee.
Use results safely
Compare scenarios with the same baseline, test sensitivity, and keep inputs conservative. Label runs and note dates.
FAQs
Can I rely on one run?
No. Test multiple scenarios to see sensitivity.
Do inputs expire?
Assumptions can get stale. Update rates, taxes, and costs and rerun.
Where is privacy info?
See Privacy Policy.
Use with care
Open the mortgage affordability stress tester, run labeled scenarios, and keep notes on what the model includes and excludes.