I'm not sure what your crusade is about. If you honestly feel you can make a quality, trouble free bike for $250 then by all means do so. Might be an interesting education in reality for you.

There is no shortage of used bikes, just bikes that meet your Americanized standards. I volunteer at charities that ship bikes to Africa as part of their ministry. They have warehouses of used bikes they mix and match parts from to make whole bikes. Their biggest problems in not a lack of bikes but shipping costs.