Internal Tool · Dealership

Deal Desk

A dealership deal sheet rebuilt from a spreadsheet. Price the machine with add-ons and tax. Finance the deal flat or by APR. Watch the margin band turn red, amber or green as you type.

3 Margin bands, against thresholds you set

0 Profit numbers in the customer view

2026

The Deal Desk app with a deal filled in. Machine, add-ons, total and financing panels on the left, and a green Healthy margin panel on the right reading 35.7 percent

The problem

A dealership prices every deal in a spreadsheet. Nobody sees the margin until the deal is done, and the sheet shows the customer every number the house would rather keep. I rebuilt the sheet as a web app where the margin is live as you type.

What it does

Machine, add-ons, tax and financing with the totals doing their own math. Flat or by APR.
A margin band that runs red below thin, amber up to healthy, and green above. Both thresholds are editable.
Customer view hides every profit number and leads with the monthly payment.
Nothing leaves the browser.

Design decision

The margin band is the only color on the page. Everything else is slate, so the one thing that matters is the one thing you see.

Outcome

Live at daviddonnell.com/demos/deal-desk as a demo. The dealership version pulls wholesale cost from the point of sale, so the margin is live before the customer sits down.

What I took from it

An internal tool earns its keep by showing one number at the right moment. The spreadsheet had the margin all along and just never showed it in time.