Sail | Yacht

I want to buy a 29-32 foot sail boat. In the SF Bay area.
What should i check as far a electrical, pumps.
And how would i go about makeing sure the keel in not all dinged up? or is there even a point to ferivying the hull

Also if a late 70’s early 80’s 30 foot sail boat is for sail for around $4000 is it doomed to have something wrong with it?