As someone who has owned a number of Ferrari's, currently owns a very nice '89 328GTB, and who is in the Ferrari business, the F355 repairs and general maintenence can and most likely will exceed the value of the car in just a few years. We have a saying that goes "if you can't afford a new one, you can't afford an old one.." While this might be something of an exaggeration, it's not far off the mark. My strong recommendation for guys looking to get into their first Ferrari is the F430 model. It has proven itself to be an extremely reliable, fast, and comfortable Ferrari, with very low service and ownership costs. It is a new enough car that it falls under the Ferrari "Certified Pre-owned" program and can be bought with a warranty from an authorized dealership, and can be covered year-by-year up to the car's 10th year. Even the first-year 2005 F430's were exceptionally good cars that I would not hesitate to buy, even with higher mileage. A 2005 coupe with 10-20k miles will typically sell for $115-125k if it's CPO, depending on color, miles, and equipment.
If you want an F355 simply because you love that particular model, just go into it with eyes wide open, do a lot of research on the model, and make sure you have at least double what you budget for repairs and service set aside. If a $10-15k service bill is something you can't handle, don't even consider it. If you are dead-set on one, buy the best one you can find, and from an authorized Ferrari dealer.