A few scholarships are available. Ph.D. students receive a scholarship which is free of tax and social insurance; health insurance is mandatory and must be paid by the student. The administration of the institute can help to find a suitable health insurance. The monthly allowance is basically 1365,- Euro, depending on family status. Additionally there is a lump-sum payment of 103,- Euro for material expenses.
The Max Planck Institute will assist in finding housing (housing[at]mpim-bonn[dot]mpg[dot]de). All information about Visa/Residence permit Ph.D. students will obtain by the administration (personnel[at]mpim-bonn[dot]mpg[dot]de).
For a sketch of the approximate living expenses, have a look at some information provided by BIGS.
The IMPRS provides support for students to travel to their home universities or to visit specialists in their fields at German or other European institutions with whom the IMPRS is connected. There is also a limited budget for participation in conferences or workshops at these partner institutions, or for short invitations of specialists from these institutions to Bonn.