Hi, I'm about to rent a couple of rooms in my house. I'd be a live-in landlord so it would legally be lodgers. There are 3 rooms potentially available, but I see from online browsing that there's a lot of advice to let to no more than 2 lodgers because above that the house legally becomes an HMO. However I've had a lot less luck on Google trying to find out what that actually means? So can anyone explain what difference it makes? So I can figure out whether it's a big enough difference to make it not worth letting the 3rd room.
(There are only 2 floors in the house)