Don Casey authored a good little book, "Inspecting an Aging Sailboat" published by International Marine and sold everywhere for about $15.00. He uses a lot of illustrations sort of anticipating that you may not have absolute knowledge of arcane sailorisms. With just a modicum of mechanical and technical skills you can use it to guide you through a "survey" surely as good as one you will get for a few hundred dollars. If you can find an experienced sailor who does his own maintenance to assist, you can elimnate most of the risk in buying an older inexpensive sailboat. With book in hand build a spreadsheet of every thing you inspect and annotate repairs or replacement costs and by the end of the process you have a pretty good handle on the costs to have a safely operating vessel. Then if you look at several boats and document each you have good cost comparisons when that beauty steals your heart and the sirene call obliterates your rationality.
Have fun looking. There are a lot of boats available so choose wisely.
ps. Remember boat is an acronym for Break Out Another Thousand.