I think you'd still want a minimum. The 1/2 acre including the house and drive and yard would be a bit much.
Fortunately, I'm agricultural. The entire code is like "try to keep your structures five feet from the property line".
I called and asked about putting up a 1500 ft2 structure. They said "come in and give us $25". I asked about inspections and the like and they responded "uh... no".
If I keep my caretaker and get the property next door, a couple mini cows might be on the table (literally, ultimately).