Looking at the prices of build kits and frames recently, I am not sure that the frame is always the major component. It may be the single most expnsive, but with $400 forks and build kits ranging up to about $1,700 (US currency) some reasonable frames may be much less expensive than what you put on them. On the other hand a lot of nice complete bicycles can be had for 5-15% more than the build kits put on them.