Rentals aren’t centrally registered. They just produce a lease signed by someone who says they have control of the house, doesn’t have to be the property owner, doesn’t have to be notarized. So just print something official and say the landlord signed it. The courts eventually figure it out as fraud anyways, but you have six months rent free, and most prosecutors aren’t going after petty fraud, so it’s mostly a risk free crime unless you accidentally occupy a house owned by the mob.