I live in a house with 5 people (including myself). I have never lived with less than 4 unrelated people. We just plian can't afford the rent otherwise.
London students are just another part of the broad London community. It's the bloody tourists that are the problem.
"I fight with love, and I laugh with rage, you gotta live light enough to see the humour and long enough to see some change" - Ani DiFranco, Pick Yer Nose
"Life 's not a song, life isn't bliss, life is just this: it's living." - Spike, Once More with Feeling
The University of Tennessee at Knoxville is the reason that Knoxville itself is a city of any appreciable size. However, the UT campus and surrounding student housing is sort of a city within a city. We keep to ourselves for the most part, as we have our own campus police to keep things under control without pulling (much) off the Knoxville PD force. We generally have our own rules and regulations, and we don't cause much friction with the city. Like I said, the student body of around 25000 is a major input into the city's coffers, and the main reason for the revitalization of the downtown area, so they aren't very hard on us.
I dunno about it over in the States, but over here it is becoming increasingly common for a student's parent to buy a property, then use the rent frm mates of the student to fuel the mortgage and then sell on at the end of the degree, usually making a tidy packet in the process.
Do you have the definition of a house guest? This is also used to get round the landlord/tenant isue, and means that the property remains a private home.