a lot depends on condition and timing. I bought a modded out sled for $.25 on the dollar. it was very clean and did not show much for signs of abuse. I have owned it for exactly 3 weeks nad have spent 8 hours fixing/changing stuff that I thought was a bit hokie. would that happen on a stocker.....prolly not, but I would spen that much time fitting pipes and tuning, so its a wash to me. I bought my sled cause I liked the sum of all the parts, I know I can make them work perfectly given some time.
some guys "mod" is "hack" to me. it's one thing to vent a sled, some drill holes, some chop holes. running boards, some guys plasma cut the old boards, others use a chainsaw.....be careful buying a modded sled if you are not a tuner or are limited on parts fund.