Good in theory... Fucked in reality.
You've signed off your own death warrant.
Seriously, I wish you good luck and all, you'll need it.
Prepare for trouble, make it double. (And then triple).
Note, your girlfriend will side with her friends in an argument.
You'll have messes everywhere.
The MOST important thing you need to do is cover ground rules ASAP.
1) Time allotted in bathroom and a bathroom order on days everyone goes to work.
2) Kitchen maintenance. Who cooks, cleans and keeps tidy? Note, you'll probably not all have group meals so you'll want to insist on, "if you've made the mess, you tidy it."
3) Keeping rest of house tidy. Assign a room to each person.
4) Have everyone contribute £2 into a pot every Monday. That way if something does go wrong and something needs replacement, there'll be cash to do so.
5) Food buying. Figure out who buys what. Sharing all food? Then share prices, otherwise buy individually and keep separate from everyone else's.
6) Don't stress too much when stuff goes wrong, which it will. Women are temperamental and are happy to sulk and pout and get angry to get their way. Don't allow this.
That may help a bit. But really, -enter funeral march-
