Of course! It is your apartment and you are allowed to have as many guests as you’d like, within reason of course. Remember that more occupants means more noise and the landlord or management does have the right to call local authorities or ask those not living in the unit to leave if you are disturbing other residents. It may be written into your lease that you are subject to a fine if you are causing a disturbance to other tenants. While the office staff may not be able to limit the number of guests you have over, they can and will find a way to slap you with fines or evict you if you are disturbing the community.