Boardroom · Calculator
Seller-finance terms
Payment, balloon payoff, and total interest on a note you carry — the math the seller-carry lesson hands off.
Your numbers
Every figure is your input. Drag or type. The math runs here — no AI.
The deal
The note
Monthly payment
on $64,000 financed at 9% over 10 yrs
See the math
Assumptions
- A fully-amortizing note at the stated rate, with a balloon (remaining balance due) at the balloon year.
- Interest compounds monthly; payments are level and monthly. No points, servicing fees, taxes, or insurance are included.
- 'Total collected' counts the down payment + every monthly payment through the balloon + the balloon payoff.
- This models the note only. It is not a tax calculation (installment-sale treatment is your CPA's) and not legal advice on the instrument.
How do we know?
The formula
- financed = price × (1 − down%)
- monthly payment = financed × (r/12) ÷ (1 − (1 + r/12)^−n), where r = annual rate and n = amortization months
- balloon payoff = the remaining balance after the balloon-year payments on that same schedule
- total interest = (payments through the balloon + balloon payoff) − financed
- total collected = down payment + payments through the balloon + balloon payoff
That math runs deterministically in your browser — plain JavaScript, zero API calls, no AI in the loop. View the page source and check it yourself.
The contrast case: what happened when we asked AI models to compute deal numbers →
Learn the grounded prompt behind this number: Structure the seller-carry terms →
A planning estimate from your inputs, computed here (not by an AI). It models a level-payment amortizing note with a balloon; it excludes points, servicing, taxes, insurance, and any tax treatment. Confirm the instrument with your attorney and the tax treatment with your CPA before you offer terms. Not investment, tax, or legal advice.