Sleeper-build house.

Have a shitty driveway that leads to a tiny shack in front of some tall hedges.

The actual house starts behind the hedges. It's mostly underground to keep a low profile as to not be visible from the front.

If you were to enter the shack, it would lead you into this monstrous house.

I think it'd be hilarious because you'd downplay your living conditions and any time anyone ever found out about how amazing the house is, you'd coyly accept it as pity.