Interactive learning tool

Mortgage Decision Impact Lab.

Move the sliders to compare a clean baseline with common pre-mortgage choices. See how added monthly obligations, changes in income or rates, and spending purchase cash can reshape an educational home-price estimate.

Start with a baseline

Use approximate figures. Everything runs privately in your browser and is not saved.

Income before taxes and deductions.
Cards, auto, student, personal, support, and similar obligations.
Down payment plus funds that may also cover closing costs and reserves.
Planning rate, not a quote or offer.
Estimated non-mortgage housing costs.
An adjustable teaching assumption—not a universal limit.

Try the “what if?” decisions

Drag left or right. The number box and slider stay synchronized.

A new payment generally becomes another recurring liability in the DTI calculation.

“No money down” can still create a monthly obligation and a new credit inquiry or account.

Higher balances can increase required payments and may also affect utilization and credit pricing.

Co-signed debt can matter even when someone else intends to make the payment.

Use a negative value to explore reduced hours, a job change, or lower documented self-employment income.

Rates can change purchasing power even when income and debts stay exactly the same.

Furniture, travel, moving, or another purchase can reduce the down payment, closing-cost cushion, or reserves.

Scenario impact Stable baseline
Baseline estimate — Approximate price supported by the planning assumptions
After your changes — No change
Added monthly debt $0
Housing-payment room —
Purchase cash remaining —
Scenario income —

Nothing changed yet.

Move one slider at a time to see which choice changes the estimate and why.

little modeled impact meaningful change major modeled change

What this model teaches

  • Monthly debt can reduce the housing payment available under a DTI assumption.
  • A higher rate can reduce the loan supported by the same payment.
  • Spending cash may reduce the modeled down payment even when DTI is unchanged.
  • Multiple individually small decisions can compound.

What it cannot determine

  • Whether a lender will approve a particular borrower or property.
  • Credit-score changes, program overlays, mortgage insurance, reserves, or compensating factors.
  • How a lender will document a specific income source or liability.
  • The rate, costs, or loan terms actually available.
Before making a financial move: ask the loan officer who is handling the application. A purchase, transfer, job change, new account, or deposit that seems harmless may create documentation or qualification consequences specific to the file.
What not to do before a mortgage → Full affordability calculator → Seasoned money and proof of funds → Compare loan programs →

Educational illustration only—not a loan application, preapproval, credit decision, or financial, tax, legal, or lending advice. The model uses a 30-year fixed principal-and-interest calculation and simplified planning assumptions. The displayed purchase estimate treats the available purchase cash as part of the price; actual closing costs and reserve requirements reduce the amount available for a down payment. Actual underwriting considers the borrower, credit, documentation, property, program, reserves, mortgage insurance, costs, and lender requirements. Consult a licensed mortgage professional before making decisions. Edward Rokotyansky is a California REALTOR®, DRE #02199079, with Wiest Realty Inc.