To survey or not to survey - my thoroughly unsatisfactory answer is "It depends".
Assuming you have found the particular boat you want, how does she look? Is the boat sparkling clean, the varnish good, the bottom clean, and obviously well loved? Do the sails look good, does the motor start when cold with a pull or two, is the bilge dry and clean, does the boat when not in use live on a trailer or in the water, does the bottom have blisters in the fiberglas? Do the winches turn easily, do the halyards and running rigging move freely, are the lifeline stanchions secure, are there broken wire strands in the standing rigging, does the back side of the wiring panel look like a mess, when you walk on deck are there soft spots on the deck fiberglas, are there signs of leaking around the windows, are the chain plates securing the shrouds to the hull in good shape, is there any rot on interior wooden bulkheads, is the boat a fresh or salt water boat? Does the interior smell of mildew, are bunk cushions clean top and bottom, are the cushions comfy, does the sink pump work, would the head gag a maggot, are the hard to access areas like under the cockpit sole and behind and under the head and under bunk lockers clean and dry? Is the rudder in good shape, does it move freely, do the rudder pintles and gudgeons look good? Does the mast look good, are there signs of stress or cracking where the spreaders connect to the mast? Has the prior owner installed accessories with care or are things jury rigged?
I do not know the H23. If she has a centerboard, does it work freely but with no side to side play or wobble. If she is a keel boat, how is the keel secured to the hull...are the keel bolts sound?
When you sit below, can you lean back and read a book for and hour or two in comfort? Will you be proud to own her? Does she stir your imagination?
Assuming you have happy answers to the forgoing inspection points, and if you have some confidence in your inspection ability, my guess for a relatively small boat with simple systems is that you don't need a surveyor. If you don't have confidence in your inspection ability, then for the peace of mind in knowing beforehand exactly what problems you're buying into, get the survey.
After you make your purchase, you may wish to get Don Casey's very good book on boat maintenance, This Old Boat.
Good luck
Hugh
