Re: buying used 1976 or 77 Mariner 40 or 44
There are a few boats manfactured under the name Mariner. Do a google search for Mariner owners group. There are two, one for the asian Mariners, one for the New Hampshire Mariners. I'm thinking you are discussing the Far East Yachts Mariner 40. There is lots of good info at marineryachts.com.
I have a NH M-28 so I will not be of much help.