We've just rented a house, been in a couple of weeks. We have the main house and the back half of the basement. The front half of the basement is a one-bed flat. The night we moved in the switch tripped and we found out the switches are in the other flat, but there is a key over the connecting door, so we're to knock, then let ourselves in if there's no reply. He's an oldish guy, seems nice.
Now it turns out we share all utilities with him. This was never mentioned before, they apply a ratio.
He has been up twice now because we haven't got the heating on and he's cold. He wants us to put it on and then turn down all our radiators if we don't need them on. It's a bit of a jig as we have four floors and are in all day.
He also said our tumble drier was going to run the bills up and he's very careful. I've told him not to worry, we will make sure his bills don't go up but arch.
Also, someone I know nothing about has a key to enter our house. Isn't that a bit weird 
?