I knew someone with the older twin 150 Yamaha's, they got 1.7 mpg on a 25 Grady White and were reliable, or so he claimed. That price sounds low, bring a soft mallet when you go and use it with the owners permission. New bottom paint can hide a world of trouble, looks like this bottom paint is worn so maybe you can see problems. I came close to buying a 25 Bertram w/o motors for $5 grand, it had a fresh coat of bottom paint. Thankfully I spotted a bent rudder and shaft in the weeds and found the boat had been dropped to dry land from slings. They had piled up the new blue bottom paint thick to cover the dents and 15' of crack down the keel.