Before moving into the rental unit, the landlord will have a property condition checklist that you will have to sign. Inspect the unit thoroughly and take notes, so when you move out you are not held liable for any existing defects.
Also, you will want to request that the landlord fix any plumbing leaks, roof leaks or water leaks and make sure that the systems such as the heating and air conditioning and water heater are all in working order.
It is a good idea to take photographs of the unit before you move in and after you move out. This way there is no question as to the condition of the unit.
Problems between landlords and tenants should be resolved among the parties. However, some landlords use management companies or attorneys to resolve landlord tenant/problems. If the unit is under rent control, then the tenant can make a complaint to the rent control board and have them resolve the issue.
You should keep copies of all your rental records such as your lease and cancelled checks in case there are any problems about whether you paid your rent.
If more than one person such as a roommate is renting the apartment, then each tenant's name must be on the lease and each tenant must sign and date the lease in the roommate rental agreement.
Each roommate is legally responsible for their portion of the rent and deposits or else roommate eviction may occur.
Domestic violence may be grounds for an eviction.
When roommates leave, the landlord must return the roommates portion of the security deposit in accordance with the local city rental laws.
Pursuant to the terms of the lease, the landlord will require a new lease to be signed with the new roommate or an addendum. The new roommate will be responsible for paying the landlord their portion of the security deposit and the monthly rent and other fees set forth in the lease. You may want to have an informal written agreement between you and your roommates as to how the utilities and cable and Internet are going to be divided if you are not equally splitting the costs.
Depending upon the terms of your lease agreement, you will need to get the landlord's permission to sublet your rental unit. Keep in mind that even though the subtenant has signed a sublet agreement, you are still responsible for the rent during the entire original rental period of your lease with the landlord.