I would inquire a little more with the owner regarding all the custom work done with the metal tubing holding the top. It appears many of the joints have been welded and gussets fabricated to reinforce the structure, etc. Yes, this can work; however, it is a sign of age or structure flaw. Just my thoughts..Also, when welding this metal, at times can experience flames or fly offs of burning metal, which can cause burn marks in the fibreglass. Also, can effect wiring housed within the tubing if roof was not removed. Just another thing to look for. Cheers & good luck.