That's not too far from me!
You will have some difficulty staying in Cy-Fair and getting enough of a lot to build a garage that big. I wouldn't give up hope, however. Have you tried a little farther out 290? I think there is a neighborhood call Lakes of Rosehill that has up to 1 acre lots, and is still in Cy-Fair district. To get there, if I remember correctly, take 290 to Cypress-Rosehill Rd., turn right (North) and go a couple of miles. . .neighborhood will be on your right. Trendmaker and maybe Village Builders are there. Might be worth a look.