Q: Is deposit recommended for the accommodations in Berlin?
A: Yes, deposit (Kaution) is necessary for almost all kinds of accommodations. Its amount is usually 1.5 to 3 months of rent. You will get it back when you leave the flat unless you caused some damage.
Some deposit-free offers can be found here - but note that these flats are more expensive w.r.t. monthly rent than similar ones with a deposit: https://kautionsfrei.de
Q: When will I receive my first monthly scholarship?
A: The first BMS Phase I and BMS Phase II scholarships usually arrive in the end of October. From November, they will arrive in the middle of the months. In the case of other sources of funding, the arrival times depend on the contract.
Q: The BMS Guidebook says that I should bring at least 1.000€ with me for the first months. Is it enough?
A: In total, you need to have at least 2.000€ for rent, deposit, semester fees and everyday living until you get your first scholarship in the end of October. This should be approximately enough if you move to a furnished flat around 20 September. If you come in the first half of September, probably you'll need at least 2.500€ in total. If you move to an apartment without furniture, and you also need to pay for residence permit, maybe even 3.000€ is necessary. Cca. 500-1.000€ will be returned to you when you leave your first accommodation. See the costs of the first two months site!
Q: Is the amount of the scholarship enough for a living?
A: Living with a Phase II scholarship is quite comfortable, the only difficult period is the first two months when you have expenses but no income yet. As for the Phase I scholarship, 1000€ should be enough, if you don't spend too much (<500€). Therefore if you cannot spend more than your scholarship, then it is really important that you find a sufficiently cheap apartment. There are many Phase I students who live from the scholarship, without having substantial financial support from their families after the first two months.
Q: How has the amount of the scholarships been determined? Is there a chance that it will change?
A: In the case of PhD scholarships, the amount (1468€ per month) is set by the German Research Foundation (DFG) that is funding the whole BMS. Unfortunately, it hasn't changed for years. As for Phase I scholarships, the amount (1000€ per month) more or less the level of salary that German students who don't have a scholarship can obtain as tutors (teaching assistents) with a 80 hours per month contract (but they might have to pay taxes and social security charges). The BMS has recently acknowledged the problem that Phase I scholarships are becoming tight, and it intends to increase the amount of these scholarships. However, this takes time. If you have already signed your Phase I scholarship contract, it is not likely that the amount will change until you finish Phase I. You should count with having 1000€ income from BMS + travel funding for one conference/summer school during your Phase I.
Q: Is there any other source of salary/funding available if I have a scholarship?
A: Further funding can only be obtained if you have a family, up to 400€ per month. About this, ask Tanja. The BMS scholarships officially exclude the possibility of doing additional jobs. However, earnings from scientific occupations up to 6000€ per year are not prohibited. This means that you may work as a teaching assistant at the universities. Also you can teach private students during your BMS studies.
Q: How can I find part-time jobs as a Phase I student?
A: If you speak German, you can apply for working as a tutor in one of the universities, which will give you almost the same amount of money as the Phase I scholarship. If you don't speak German, it will be harder to find an offer that is appropriate for you. But from time to time, the BMS Office receives public or private offers for teaching Mathematics or mathematical classes at the Berlin universities in English. Keep your eyes open, and if you don't see any such offers for a while, feel free to ask the BMS Office about this!
If this is an option for you, you can also find a part time job in industry, which is usually a bit better paid than to be a tutor, but of course, usually less purely related to mathematics, but could be for example something in the field of Data Science. Search for positions as a "Werkstudent" or "working student". In most Berlin companies, german skills are a plus, but it is not everywhere an absolute requirement.