I just purchased a 2000 with a little over 100k for $4,900. Stored inside and only driven 10,000 in past 10 years. Owned by older couple that passed away and son just wanted to get rid of it. New Jasper tranny 7,000 miles ago. Had a feeling I would need to replace the ball joints because the steering was a bit loose. Also, new plugs and boots would be due because of the age.
If those things have not been replaced (receipts), here's what you need to consider:
Upper and lower control arms with ball joints (mechanic said needed to get control arms with the ball joints). This was around $2,000
Plugs and boots. This was more labor than anything. $700
Serpentine belt and tensioner. $300ish
Change front and rear diff fluid, and transfer case fluid. $200ish depending on shop rates.
Check the tires for cracks in the sidewall. If they are older, replace. $700 to $1,000.
Mine was the EB model with air suspension. I did the coilover conversion myself since it was starting to sag. $400 to $600.
I started with a very solid rig, but it needed some maintenance. I'm into it about $8,000, but plan on keeping it for another 100,000 miles.