The rent is mostly determined on the value of the lease, which is again determined by location, property type, size, fixtures and condition of the property.
In some cases, the rent depends on whether the lease is part of a larger apartment complex or located in a municipality, where the rent is regulated.
The landlord can raise the rent if it is currently too low, compared to the rental value. He or she can also increase the rent when facing an increase in taxes or when improvements have been made.
However, If the landlord wants to raise the rent, you, as tenant, have to be given notice in advance.