How old do you have to be to get a home morgage?

how old do you have to be to get a loan for a home. im 18 going to be 19. Right now its a really great time for first time buyers. this is my second year workng at aerospace making 80,000 a year. can i apply for loan or am i to young or need more years of work. Also if im to young can i be a co signer. also i have no credit what so ever unless you count my checking and savins account. i have all money saved up for down payment. what is the perfect way to build my credit