I would say if you want to save money to search around at garage sales for old road bikes. Spring cleaning time is approaching so you should have some good luck. Find a bike with workable parts and you can get a decent fixed rear wheel for ~$80 or a pretty good wheelset for ~$140. Better idea than converting a probably-rusted-on-the-inside-too frame, and will have more character (and leave you with more money to perfect it) than one of those off the rack ones.