I guess that since it has been painted at one time on the bottom of the hulls, that the gelcoat has likely been worn away down to the fibreglass layer. Have a good look at the bottom of the hulls, if the bottom of the hull is very flat, say any more than an inch wide, there's a chance that it's been worn away so much that it started leaking and that's why the repairs have been done. Obviously if the repairs don't look good, then it's going to be a problem.
I can't really comment on the prices in the USA, but it seems like a cheap boat anyway, and at the end of the day, you generally get what you pay for.
As for the rules, I understand that you are permitted to re-build a worn down hull, as long as it's to the original hull shape and as for painting, as long as it's not deemed to be a friction reducing measure, you're OK. That's my idea, however you can look at the rules on
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