It is a Sea Rider and they are arguably the best small ribs made, they are very sturdy and have been in production for a long time and are very expensive new. This one is a long way from that however!.
The hulls are fairly bulletproof and it looks like you have all the seat mouldings. I have just bought one in a similar state to renovate so maybe we can exchange notes .
In answer to your questions
2) What should I look for with regard to an inspection I'll give the craft next week?
Delamination. check as best you can that the gell coat is still firmly attached to the rest of the fibreglass.
Check that the fixing points are still good for the consoles etc and also check that the transom is still firmly attached to the hull/Tubes.
If all that is OK then everything else is easily renewable. I'd also check there was no frozen water inside the hull.
3) Are new "tubes" very expensive if the tube proves to be trashed? About 1500 to 2 k over here
4) What should I pay for this boat? (impossible question, but I had to ask) In that state and providing that answers to question 2 are favourable then maybe 500 to 1000 bucks anything less than 500 bucks and it becomes a real good buy
150 hp is a no no But looking at you location and considering it's got the ability to get f f f f airly cold out there I'd consider sticking two 50's or 60 twins. The weight balance might be tricky however
The transom is rated to 90 HP but you could emulate David Mannng who really beefed up his transom and stuck a 115 on th eback......waaheyy
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