XJs are fun....we all know that haters are gonna hate.
Anyway, I know you said it's clean, but get under and look carefully for rust. Bang on the rockers (especially the area under the rear doors) hard to see if there are any weak spots that have started to rust from the inside. The rear upper shock mounts are notorious for being a royal PITA to change (cheap studs rust / break easily), so plan on that not being a completely simple swap.
What lift is on it (brand and size)? Some of the cheap lifts cut corners on things that aren't needed 100%, but will definitely compromise ride / handling / reliability (such as trackbar relocation brackets or poorly made adjustable trackbars).
Being that it's a 2000 it has distributorless ignition (only on 00 and 01 XJs) as well as a greatly complicated exhaust emissions setup (same 2 years). I don't remember all the specs, but I think it runs 2 pre-cats, one reg. cat, and either 3 or 4 O2 sensors (compared to the 96-99's 1 cat, 2 O2 setup). These replacement parts for the 00-01 setup are far more costly. Personally, I would look for a 98 or 99 if you like the later body style, or a 96 if you like the earlier body style. Going that route, you have more parts in common with other cherokees, and likely less headaches with replacement parts.
- Justin