Of course knowledge comes with experience, so I wouldn't belittle someone for asking for advice. I'm always a lil' wary of buying used sails. Because unless they came from a boat that was parted out, another sailor traded or got rid of that sail, probably because there was something wrong with it. Maybe the sail they had was too big or didn't fit right (ie: the foot was too low or a 150 genoa might be too big) but I would look closely at the sailcloth & make sure its not worn out. Its also hard to determine whether a sail has lost its shape from being overtentioned by a halyard by someone overzealous on a halyard winch. I would also inspect the outer U.V. Cover on a genoa very carefully. If the cover is worn out it can cost many hundred of dollars to replace it. Unless you're on a really tight budget, I would save money for a NEW sail, that will last a lot longer, give you better performance under sail, & a better investment. When shopping for new sails look closely at the oz. weight of the sail cloth. You may not need heavy offshore sailcloth, but lighter weight sails will not be as durable. Most sails have a good working life of 10+ years, but I've had good quality North Sails on my last boat that were over 20 years old & still performed well. I also like UK Halsey & Ullman sails for durability. The problem with a local sail loft is that its hard to compare them to the big lofts in terms of quality. Sails are so expensive that I would place my bet on a sail from a well known loft. When it comes to sails, you really do get what you pay for.