Man, the only time I ever had an inspection in a place I was growing I had my medical card so I didn't see any point in hiding my 4x4 tent in the corner of the living room. They tried to tell me I couldn't grow, but then I pointed out that if they tried to evict us based on that, it was discrimination against a medical issue, and that is illegal. They got the hint and left us alone till the lease ran out (then refused to let us sign another one. Lol). If I were having to hide mine, I would also go the rented van route. If they aren't too big, maybe you could rent a van instead of a truck. That would be better insulated and wouldn't be too much of a hassle, imo.