With an interior that is in as good shape as that one appears to be, you're already ahead of the game since a big chunk of change can be dropped on a new interior. Carpet is a much less costly item to upgrade and can be DIY. Just depends on taking a chance that you won't be surprised with some major motor repairs. If you could rule out salt-water use and any major engine issues, it may be worth it. Heck, I've seen folks buying 'project' boats on this forum for several thousand and then having to completely refurbish every aspect of them, ie. hull, interior, motor, and transmission when clearly the amount spent could never be recovered when sold, and taking a heck alot of effort along the way (not that there is anything wrong with that!). I've got an '88 with identical motor (owned for 15 years). It has been very durable and trustworthy. If you wait long enough, someone else may make the decision for you though.
1988 Tristar 190 Sport, 351W w/GT-40's, 1:1 Velvetdrive