@kbgunn ,
that's a $5 to $8K repair depending on who you ask and what part the country the yard is in (I know you are in TX). It isn't just the fiberglass work, it's also finishing (fairing, plus gelcoat or paint). Its totally not worth it for an early 80's Catalina 30 if you are paying someone else to do it. Even if you assume just $7K being the total cost of purchase plus repair, there are far better boats in the 30 foot range that can be had for that price including newer year Catalina 30's.
Now, I never shy away from work and you can be sure I would over engineer the crap out of it.... But, I would only consider taking on that project if very specific criteria are met;
1. You'd have to get that boat dirt cheap... really cheap. If the owner wants to haggle, walk away.
2. I would need my own property large enough to move the boat to where the work will be done, my own tractor or other heavy equipment, and/or a VERY reasonable priced boat hauling service (which I don't think is possible).
OR
If there is a very affordable DIY yard in the area (the rent has to be cheaper than keeping her in a slip).
3. I gotta have the time to do it. I've already been through Grad school while trying to restore an old Catalina so I don't want to experience that again.
The work is doable... It just takes a keen eye to get the fairing right, especially at the sheer where the rub rail attaches. Keep in mind you might have to paint the entire hull, but I've become more inclined to use Gelcoat than paint. I thinks its better to Gelocat the repair area and do a wet-sand/cut/buff restoration on the rest of the hull.