First, please allow me to say this without hurting you. One should not breed and/or sell Yorkies strictly to raise money. That is sad, irresponsible and selfish especially considering how many poor, unwanted Yorkie babies there are out there!!!
Yorkies are a very precious breed. They need lots of love, individual attention, proper and regular vet care, good food and they should be raised indoors as part of a family. Yorkies should never be left outdoors unattended for any length of time even in an enclosed area.
Please reconsider what you are about to do!! There are much better ways to earn money for college. Have you tried applying for grants, scholarships, student loand or getting a job? These would be much better way for you to accomplish your goals. Best of luck to you