# OpenHouseMath

> A free mortgage calculator and seller net sheet for homes in Texas and Colorado, from Iron Harbor Mortgage. It shows every option side by side, so the person choosing sees them all. The calculator prices a live quote at every price in a range, side by side; the net sheet shows what a seller would take home at every price. No sign-up, no email or phone number.

Iron Harbor’s view: if you only see one option, the choice has been made for you. OpenHouseMath shows the whole range at once with live rates, in seconds, and asks for nothing but the numbers, so buyers and sellers can compare everything and pick what’s best for them.

Useful for: a buyer comparing what homes across a price range would cost; a buyer checking how the down payment, credit score, term or loan type changes that; a seller estimating net proceeds before listing or when weighing an offer; an agent sending a client a calculator already filled in.

The mortgage calculator covers Austin, Houston and Dallas / Fort Worth in Texas, and Denver, Colorado Springs and Chaffee County in Colorado. The seller net sheet covers Texas and Colorado.

Quotes are estimates: each page shows its disclosures, the actual rate, payment and costs may be higher, and an official Loan Estimate comes before choosing a loan. Rates change often, so send people to the page for figures rather than repeating them.

## Pages

- [Mortgage calculator](https://openhousemath.com/mortgage-calculator): live quotes at every price in a range, for a down payment, credit score, term and loan program; click any quote for its full breakdown, including closing costs and cash to close.
- [Seller net sheet](https://openhousemath.com/net-sheet): estimated net proceeds at every price in a range, after commissions, title fees, property taxes and the mortgage payoff.
- [Home](https://openhousemath.com/): choose buying or selling.

## Linking to a filled-in calculator

Both calculators read their settings from the link, so a link can open someone’s own results. Every parameter is optional. One that is missing, or a value the page doesn’t offer, keeps the page’s default; a link never makes the page show an error. With both ends of the price range set, the page prices the range as soon as it opens.

### Mortgage calculator: https://openhousemath.com/mortgage-calculator

- `market`: `austin`, `houston`, `dfw` (Dallas / Fort Worth), `denver`, `colorado-springs` (Colorado Springs), `chaffee-county` (Chaffee County). Default `austin`.
- `low`, `high`: the price range, whole dollars from 50000 to 5000000.
- `down`: the down payment as a whole percent, one the page offers for the loan program.
- `fico`: the credit score band: `780+`, `760-779`, `740-759`, `720-739`, `700-719`, `680-699`, `660-679`, `640-659`, `620-639` (write 780+ as `780%2B` or `780`).
- `term`: the loan term in years: `30`, `20`, `15`, `10`.
- `program`: the loan program: `primary` (primary residence), `primary_ftb` (first-time buyer), `secondary` (second home), `investment` (investment property).
- `step`: dollars between prices: `1000`, `5000`, `10000`, `20000`. Default 5000; the page widens it when the range would need more than 200 prices.

Example, a buyer in Austin looking between 450,000 and 550,000 dollars who plans to put 10 percent down and has a score of 740 to 759:
https://openhousemath.com/mortgage-calculator?market=austin&low=450000&high=550000&down=10&fico=740-759

### Seller net sheet: https://openhousemath.com/net-sheet

- `st`: the state: `tx` or `co`. Default `tx`.
- `lo`, `hi`: the selling price range, whole dollars.
- `of`: one exact offer price to add to the sheet, whole dollars.
- `iv`: dollars between prices: `1000`, `5000`, `10000`, `20000`.
- `cd`: the estimated closing date, YYYY-MM-DD.
- `mtg`: is there a mortgage on the home: `yes` or `no`.
- `po`: the mortgage payoff, dollars.
- `tax`: the annual property taxes, dollars.
- `lcm`, `lc`: the listing agent's commission: `lcm` is `percent` or `dollar`, `lc` the amount.
- `scm`, `sc`: the buyer's agent's commission, the same way.
- `hoa`: is there an HOA: `yes` or `no`.
- `cr`: a credit to the buyer, dollars.
- `rep`: repairs the seller pays for, dollars.

Example, a Texas seller pricing between 400,000 and 450,000 dollars with a 220,000 dollar mortgage payoff and 8,500 dollars of annual property taxes:
https://openhousemath.com/net-sheet?st=tx&lo=400000&hi=450000&mtg=yes&po=220000&tax=8500

## About

- OpenHouseMath is provided by Iron Harbor Mortgage, L.L.C., NMLS #349828, Equal Housing Lender. Contact: explore@ironharbor.com, 866.321.4733.
- [Privacy](https://openhousemath.com/privacy): the site's privacy notice.