I have bought many a complete bike to get a series of components, then either built the bike back up with other components and sold it, or sold off the components. It is a helluva lot cheaper to buy a complete bike that it is to try and build one up from scratch. Example, I have a steel frame that I am building a city bike up for my son with. Parts were going to total out close to $700 not including any labor. I could have purchased a Torker Graduate for ~$450, gotten the wheels and some other odd bits off of it, thrown a set of single speed wheels on it, sold and recouped most of my cost. Price everything out a couple of ways then do what makes the most sense for you.
Aaron
