I'll go first and I'm a little ashamed. I was 26, atelier still in my legs, and a small gallery in a neighbouring city offered me a show. I signed the contract the same afternoon. Didn't read the exclusivity clause. Turned out I'd given them 18 months on all sales, including anything I sold privately, in any region in France. My first dealer taught me exactly one useful thing: that mistake.

Who here signed something on the way up they'd never sign now? And what did it cost you, or what did you learn?