I recently purchased a 1983 Tanzer 27 that has been sitting for a number of years. I am most concerned with the thru hulls and stuffing box. Other than the obvious, dry rot, bulging drain hoses etc what should I be looking for?
A careful inspection of the thru hulls would be prudent. Check the condition of the hoses. Check the action of the valves. Do they operate smoothly or are they stiff? You didn't mention if they were bronze or Marelon. If you are really nervous as to whether or not they seal when closed then put together a test rig that allows you to fill the hoses going to the thru hulls with water. Close the valves and pour water into the hoses and see if the thru hull leaks. Of course there will be a pressure difference when the boat is in the water but I don't think that over rides the validity of a static test.
If you don't have any maintenance records then just go ahead and repack the stuffing box. It is generally not a pleasant task given the limited access. Better to do it on the hard.
Make sure you check the standing and running rigging thoroughly. Was the boat stored with the mast up or down?