i bought my supra in the same circumstances, high hours, but i bought it for the it may run price. I'm A Marine engineer and That is the big deal if its salt water 1100 hours it trashed, if not(freshwater) i could still have some life left. The price isnt the best for the year with a possible rebuild. I would present the facts to owner and do a compression test and take an oil sample let it sit for several minutes and see what it looks like. Other things i would try to see condition of the PCM power pacs if they are trash (personal experience) and they are 500 to replace with a retro-kit that is all around a better set-up. 8500 for a 21 year old boat ehhhh condition is everything pics would be a good addition to thread. In my opinion i would start an offer of $6000 and go as far as 7500, but that's me.
VR,
IT's just a boat - You need to love it!
Caress Me down - 1991 Supra Sunsport