Variable assumption formula help

I am trying create a formula based on assumptions. I sell cars... And I want to calculate an assumed transaction price vs my ask price. I feel it to be a safe assumption that if i have a car is listed at less than 20k, the difference between my "ask price" and ultimate transaction price is 1%. If the ask price is bw 20-30k, typical transaction is 2% off ask. 30-40k, safe assumption is 2.5% discount...etc. my question is, if I enter my inventory with ask price, how can I produce a formula that makes those percentage assumptions based on the investment values? I'm assuming it's an IF formula...but I can't figure out how to make it work. Can anyone help? Thanks guys.

Welcome to the forum, can you change your title to more specific one.

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