craigslist clone...A GOOD ONE!

I am looking for a cline of craigslist that looks and functions with the features of craigslist. The best would be someone that has already created this script. I need it to be affordable caude it is being used for anexperiement. I need it to be php and bug free. Also needs to be able to be modified in the future. Again I am looking for a craigslist clone...not those crappy free classified scripts that i can download for free. If this job is up your alley or you have something created you think i might like contact me and or bid. I do not have alot to spend considering this is for non profit. Matt