looking for a little help about csts

so a guy is selling some tein csts on craigslist. he wants 1000$ and keeps rejecting my offers of like 800$. if you know anything to help me get him off the price let me know. Is 1000 a decent deal? he said they have 10k of use and were on a 04 accord i think. it also comes with a truehart camber kit for the rear. i know new they cost like 1600. but is it bad to get them used?