Hi,
Congrats on the new to you boat. I'm guessing that the 'dump it' comment above refers to the notion that sometime, a 'free' boat can often be a lot more expensive than shelling out some cash for a boat in better shape. Not always true....if what you have is in good shape.
Post some pics of the boat and motor, and invite comments - there are lots of users here who can take a look at it and id any obvious flaws in what you have. A boat that age may have some real problems, or you may have got lucky.
Take a look through some of the fiberglass restoration threads; that will give you an idea of what can go wrong on a boat like yours, and what is involved in fixing it.
For a quick few things to look at: check the floors. Any softness will mean you will need a floor, stringer and probably a transom replacement (some $$ and lots of work). Check out all the mechanics - does the motor turn over, do the steering components work. Check out the trailer carefully - make sure the frame is in good shape. Check out the hull for cracks or obvious signs of damage. Look over the seating - if it is all shot, then you are looking at a potentially expensive repair. If all these things are good, then this may be a boat worth keeping. If you have problems in all these areas, then don't start putting money into it: sell it off for parts. If you have problems in some areas, but not all.....well.....then the resto threads will give you an idea of what is involved.
Lastly, make sure you have title to the boat before you even consider trying to fix it up.
Best of luck, and welcome to iboats. If you do decide to keep it, lots of good advice and help on here.