I live in a building with students and have no problems at all. concern is particular situations like I've seen first hand such as a landlord deciding to modify 2 bed apartments in to 3 or 4 bed apartments, and renting out the tiny rooms individually for insane money. maybe it's fair game but to me it's shady. Weather or not the tenants, student or not, are cool with it is not my concern.

Personally I feel limiting 3 per unit is asinine, and discrimination against students or marketing apartments only to students is wrong. Landlords will likely find ways around it anyway, though. That said, I feel there should be a square foot per person limit for the sake of safety and consumer protection which applies to all.