Something is wrong with that boat, for a 2004 that paint should not be peeling. It is not anything structural, just paint, typically awlgrip is what builders use, not sure what Grady uses. Nonetheless, it should last years, not 5 and peel, so something is wrong with that paint or something happened to that boat that the owner is not disclosing and is hoping someone will over look. As far as the bolt in the transom, it is hard to tell but there is some rust and looks like a small crack or two, those cracks would surely need to be repaired and just touched up to prevent water from seeping in, a survey can tell you if there is actually any transom damage or if they are just stress cracks which need a little attention due to their location, which they likely are, but still need to be checked out.
The only true negatives to the peeling paint inside the hull are that your going to have paint chips throughout the hull, some bigger ones could potentially block the passages from compartment to compartment and stop flow and could retain water in the hull, or if something went wrong, possibly cause the boat to flood. The other negative is the purpose of the paint is to allow the inside of the hull to clean easier and stay clean, rough fiberglass seems to hold dirt on its surface a lot easier and is harder to clean, plus any chemicals that you use can and will to some extend effect the resins in the fiberglass on the surface, it would take tons of chemicals to have an effect, but it is something I'd avoid if possible. The paint essentially is a barrier to protect the fiberglass below, much like gelcoat does on the topside of the boat. Builders use paint on insides because it is easier and quicker to apply and also cheaper, also no one waxes the inside of a hull so there is no need for a higher quality glossy gel coat there, paint is better suited for the job.
Coming from a boat designer, I do not see any structural issues with this, but would personally shy away from this boat because this should NOT be happening, almost ever, especially on a newer boat. If you were to get a great deal on the boat, I would be cautious and highly recommend putting some time over the winter into scraping off a bit of the peeling paint, clean the surface and then roll on awlgrip paint to take care of the issue, it isn't something I would just forget and leave alone, those paint chips in the hull would worry me that the boat is not draining properly. Best of luck, hopefully you can find a boat out there that suits your needs and with less issues.
