What actually happens after I put my address into one of those instant cash-offer sites?

Entering an address into an instant cash-offer site triggers an automated valuation model that estimates a price from recent sales across a wide area, not a walkthrough of your home. The number is typically not final, it gets adjusted downward after an inspection turns up repairs, and a service fee is usually built into the offer. You are free to compare that number against what the same house would likely bring on the open market before deciding. Joel Boss can run that comparison at no cost.