I suspect that the answers you'll get here will be somewhat biased. My sense is that the majority of us are do-it-yourselfer's to the maximum extent of our abilities, and that's one of the reasons we're inhabiting sailnet. "What, let some stranger strip my bottom paint, I'd sooner..."
Val's thoughts seem quite solid to me. You have nothing to fear, as a rule, from buying an older boat after careful research of the particular boat's build quality. What you are confronted with is the choice between a true project boat and the prospect of earning your boat building merit badge, an immaculately kept and upgraded specimen with attendent price tag, and the somewhere in between we mostly end up buying. What you'll never find is a boat that needs nothing done. They start needing work the minute you purchase her. That is, if you want to keep her at current condition.
The real trick may be on deciding what you are willing to tackle and what you just feel you must have professionally done. Some guys do make their own sails. Others, who purchase their sails, think nothing of tackling a bottom job or painting her. While some of us may not know too much about sweat equity as it applies to our house, most of us rely on it to defray what otherwise might be a prohibitively expensive passtime.
My particular boat has never been painted, and if I wanted a showpiece I'd have painted her already. Instead, I sail her and keep up on the stuff that, left untended, will cause her to deterioate. The nicks and such in the gel coat are filled, the colour doesn't match as well as it might, and she doesn't look too bad. But then I know that once I paint her, it will be paint for life, and I'll feel a whole lot different about rubbing the dock than I do now. And I'll be the first to admit that I haven't gotten around to trimming the excess sealant from around a couple of cleats I rebedded this spring. I bought a 1973 boat that I could upgrade and maintain in a manner than allowed me to sail every summer and not pay through the nose for what needed doing. Each year I tackle another project or upgrade, weighing it's completion against lost time on the water. Appearance, while decent, is way down on my list from functional upgrades and being on the water.
I heartily recommend Don Casey's Complete Illustrated Sailboat Maintenace Manual. The first "book" in it is, "Inspecting the Aging Sailboat". It will give you valuable information on what to look for prior to deciding to survey a boat. The rest of the book will tell you how to fix things and, better yet, give you an idea of what things you can reasonably expect to do yourself. All in all, a good investment.
“Scientists are people who build the Brooklyn Bridge and then buy it.”
Wm. F. Buckley, Jr.