The rent of the rooms are calculated according to the housing valuation system, also called the points system. Every part of the living space, such as surface and several facilities (sanitary, the kitchen, outside, etc.) gets points. Do you have your own bathroom, toilet and/or kitchen? Then this room gets more points than a room with shared facilities. Combined, these points amount to a maximum rent. This way, you always know you pay the right amount for your room!
See here what the service costs contain:
You will receive an annual final bill in May, regarding the actual made costs over the period of January to December. Depending on this, you will get money back from us, or you will have to pay us some more. There will be no final bill over the contributions tv/radio, property taks, Elbuco and internet. The amount you will pay for service costs can, just like the rent, change annually.