There are two main possibilities for housing. You can either live in a student hostel called ‘Studentenheim’ in German language or you can rent your own apartment. In Student hostels the rent depends on whether you are sharing the room with another student (around € 150/month) or have an independent room (between €190 to €240 depending on the Studentenheim where you live). The hostel rooms are equipped with furniture including bed, writing table, small chest of drawers etc. While the hostel management of few hostels may provide a quilt, pillow and bed sheet, it is not necessary that you will always get it. So please check with your hostel management. At times there is a security deposit around €300 that you get back once you vacate the room.
In Bonn, single room costs anywhere from 200 to 300 euros, while double room costs from 150 to 250, depending on the hostels. In any case double rooms will be cheaper in the same hostel than single rooms. As stated earlier, some of the cheaper rooms do not provide you bed sheets, pillows and quilts, so it´s a good idea to bring a few bed sheets at least. You can buy a quilt from here, they are not expensive. Also room sizes in Bonn are usually smaller, mostly 12-20 m² for single room and from 20 to 40m² for double rooms, again depending on the hostel. Bigger ones usually cost more.
You can also get private accommodation. You can find one through property dealers, but they usually take 2 to 3 months rent as commission (this is same in other cities as well).
If you want to live in your own apartment then there is a big variation in rent depending on the size and location of apartment. To give you a rough idea an apartment of 45-55 sq. m with two rooms (not two bed rooms but total of two rooms which means one bedroom and one living room) with a kitchen (may or may not be separate, at times it is part of living room), toilet, small balcony is about €500 Euros. Usually the heating and electricity are extra but at times they are also included in the rent depending on how you complete the deal with your landlord. But let us tell you, finding an apartment is not an easy job because of multiple factors viz. language, being foreigners, having less information about the area etc. But in our opinion, in the long run having your own apartment is better than living in a student hostel. Not only that its cheap but you have more freedom as well.
If you want to get better idea about apartments then look at this web site (Kalayado) . Translate the web site using Tools, then choose the ‘parameters’ that suit you and then it will show you a range of apartments and their rents. Since you are not aware of the abbreviations they use on the web site and some details of Renting Business in Bonn, so chances are that you will make mistakes but its ok to give it a try.
For those who are planning to bring their families, there is also an option to get subsidized housing if your earning is below than some certain level. Once you reach here, check with Stadhaus and similar organizations who help students in finding accommodation. Your seniors might be able to suggest some thing as well.
Forms for applying:
Some Useful links:
A (sample) document about info of hostels, there rents, distance from universities, community, etc
http://docs.google.com/View?id=dxr8mbm_9d84wzz7v