You may need to get a certificate to show that your property is fit for habitation. Certain properties don't need to get the certificate, but it is an offence to fail to apply for one if your property isn't exempt.
All rented properties must, at the very least, meet the basic fitness standard. However, even if your home meets the fitness standard it could still be regarded as unfit by inspectors from your local council. You should try to maintain the property to a standard that you would be happy to live in.
The Rent Officer, rather than individual landlords, sets all rents for protected tenancies. If a landlord wishes to increase the amount of rent which can be legally charged on this type of tenancy, s/he must request a Rent Determination from the Rent Officer.
You may be a protected tenant if you have been living in the same property since before 1 April 2007 and the property you are living in is, or was on 1 April 2007, in a poor state of repair. If you're not sure whether you're a protected tenant or not, there are a number of ways to find out.
The Rent Officer for Northern Ireland is responsible for setting rents on rent controlled and protected tenancies. If your landlord is charging more than the Rent Officer has allowed, you could be entitled to have this money back.