I'm in the process of looking for a road bike. Up to this point in life I've never really had a bike fitted to me and I currently have on old Schwinn mountain bike which I know is too small for me. I've taken some measurements at home and used one of the online fit calculators and it says that I need a 59cm frame for a road bike. (6"2' 35'ish inseam - long legs) My question is...how much flexibility do I have with this number? Can I come within a few cm's of it and still be comfortable on a bike or do I need to adhere to this quite closely? I'm presently in the market for a used road bike and I thus don't have the ability to go and buy the perfect sized bike but I also don't want to pass up a sweet deal on a used one that I might see that measures 57cm or 61cm. I'm new to road biking so I'd appreciate any advice you veterans can give.

Thanks!