Well, That certainly looks disheartening. There are a lot of surplus FC's for sale in CA right now. Most are in pretty bad shape. Heat and age have weakened the glue bonds. The thick deposit of glue on the speed tube seams is from poorly made repairs. My PVC Futura had similar issues. The PO layered glue upoun glue. The two part glue does not bond to old glue. The thick deposit is hard to remove using heat or solvents. I recommend dremel abrasive wheels. Slow work becuase the wheels are small, but there is less chance of further damaging the material.
The floor seams look like they are just coming apart and should be easier to work with since there isn't so much glue deposition. You do need to work all of the floor seam apart that will separate without damaging the surface layer of the material. I did not remove my entire floor as some recommended. The sections with good bonds have not failed yet and it has been almost 5 years. However, if it will come apart, pull it apart. I fill my boat with a couple of inches of water and check for leaks once a year.
Whether the boat is worth repairing is a personal decision. My Futura needed extensive repair including rebonding much of the transom. I took my time (never overlapping repairs until the underlying glue job was cured) and put a lot of effort into it. If you have the time and the skill repairing seams and holes will give you a reliable boat.
This is the type of abrasive wheel I used.
Prepped to glue the floor seam.
Old layered glue is a pain to remove, but glue does not stick to old glue.
You have to do whatever it takes so that repairs lay down nicely, no tension on the material! It is a one shot process with no adjustments. This pucker at the floor to tube to transom was difficult.
I let the boat get warm and then stretched it between my car and truck to get the pucker out.
Obviously, if you are going to do this much work you want it to last. Prep is everything! Buy a cheap hygrometer and watch the humidity. The two part glues are hygroscopic and moisture results in a much weaker bond. Don't rely on the weather report. Your immediate local conditions may vary significantly. As long as the material itself isn't breaking down anything can be repaired. It is just an issue of how much work it's worth for you to do it right.