Inside the cabin the mast support post also serves to enclose the cabin slide door which separates the head and forward berth from the rest of the salon. If the door does not slide freely there is a good chance that mast support post is bent. With a 35 year old boat certain curvature is to be expected but if it is excesive it will likely need to be replaced. When the shrouds are tightened the place a lot of dowward force to the top of the post but if the post bends it will not be possible to maintain the rig properly tuned for any length of time. In those boats, the bilge area is real shallow which may result in water spilling out when the boat is heeled under sail. A float switch for a bilge pump does not work well in it so an electronic automatic pump would be recommended. Check the hatches, if they are the original ones they are probably broken and will likely leak. They are not standart size and replacement can be difficult and expensive. Do not worry about the portholes as they are still being manufactured by a subsidiary of Bomar and their price for new ones as well as for parts is reasonable. Check the through the hulls as those boats came equiped with gate valves. Insure they have been replaced with ball type valves or at least that they are in good working order. Hoses should be double clamped. Besides the standing riggin the other items that are of primary importance are the engine and the sails. Compare the asking price to other h27s in your market. In fair condition I would say between $3,000 to $7,000 depending on the market area and additional equipment. These boats were overbuilt and are very sturdy, they are a good and roomy small coastal sailer and may provide you with many years of service. Good luck.