opinions wanted on value

I helped do the lift, and have know this jeep since it was bought about 5 years ago. The motor was rebuilt due to a dumb ass putting 20w50 in and spinning a rod bearing. The mechanic talked him into a full rebuild. As for running and driving, i drive it about once every three months and everything seems fine. It runs through all of the power ranges fine. I have never had a problem with the TB swap. Is that normally an issue?

He is asking $3500.00 but I’m thrid in line for it. I thought it was a decent price, but wanted other opinions.