How much would a copper repipe be for a 2 bathroom house about 1500 sq ft?

Sorry, but it is impossible to give an accurate quote over the internet. To many factors to take into account. The only way to get an accurate quote is to contact several local plumbing companies and have them come take a look at the job. Material mark up, hourly labor rates, accessibility to piping, etc etc etc make a huge difference from area to area. Are you dead set on copper, or have you looked into repiping in PEX? A complete repipe in PEX is going to cost quite a bit less than copper.