Hull Problems - how to tell

I am looking at purchasing a boat that the dealer said needed to repairs to the jell coat and rub rail. He insures me that the damages were only cosmetic and have since been restored to original condition. How much should i be conscerned about structural damage and is there a way to tell if there is any? It seems that if they needed to repair the rub rail that something major might have happened.

Your thought?

The fact that the dealer would make sure you know about the repair seems to show that they have faith in the quality of it. Done properly, fiberglass and gelcoat repairs are not a problem and last the lifetime of the boat.

Hire a surveyor! He will have an infrared camera that will show every crack and potential soft area! It's worth the $300!

I bought a 2000 X-Star with a completely refinished hull. They completely removed the engine & drivetrain, flipped the boat upside down, finished with totally new jelcoat, and then reassembled. I never would have considered buying without a guarantee, but it seemed good and has held up for 4 years just fine.

Of course, we meticulously clean every time and wax pretty often, but I doubt that makes for much better wear. Just trailering it instead of keeping it in the water for long periods of time is probably the main reason why it is holding up well.