Good luck building anything in the wasatch and keeping it a secret. You would even be hard pressed to keep something like that secret in the Uintas. The only place you could just build something in Utah and no one would know is all south of I-70 and east of I-15. But you could go a head and try, if you just built a small bungalo you could probably hide it pretty well or just stay in the numerous cabins strewn across the wasatch. Hell there are two right above layton you can stay in whenever you want, us locals keep it pretty well stocked with propane.
I suggest you read "Shelters, Shacks, and Shanties" by Danial C. Beard before pulling any shananagans. Your mind will be blown.