Four real cars. All four already sold on Bring a Trailer. Every price is real.
One guess, four answers. Type a price. It gets checked against every car you haven't solved yet.
Read the arrows. ↑ means that car sold for more, ↓ means less. An orange arrow means you're within 25%. Within 10% solves it.
Ten guesses a day. Solve all four. Fewer guesses is a better score.