I bought a boat that had 60 hours at 12 years old (averaging 5 hours per year) but was kept/serviced at a dealer and had regular maintenance and winterization done every year. It never sat un-used, just used very short periods each week when it was used. I've had no problems other than normal (now 15 years old) boat maintenance. Your experience may be different.
It sounds like it was already taken on a sea trial (in water test) and performed ok. That is a good start. Depending on how old the fuel really is, adding premium would help with extra octane to make up for the old gas that is now not so good. If it is really, really old it is probably worth it to have it drained to start with fresh fuel.
I'd also recommend a new impellor just to be safe. And yes, check all the hoses to make sure they are ok. I'd also recommend the engine and outdrive oil change if it wasn't done in the last year.
I wouldn't go so far as to change all the plugs, wires, dist. cap until you see how it runs. But then I wouldn't go too far out until you know how it runs and get some more time on it to uncover anything that may come up. All those things are good maintenance items and should be done eventually. If it does seem to run rough a carb re-build is probably next.
I add "Sta-bil" to my gas each time I fill up and have had no fuel problems, I'd recommend something similar that is available down there. I have never used any fuel system cleaner.
Welcome and good luck.
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Terry
Current: 07 Crownline 255 CCR cuddy - 350 Mag MPI/B3 "Casi Cielo"
Previous:97 245 Sundowner 5.7GI/SX
Tow vehicle: 1986 GMC 2500 Camper Special 454/TH400
