How much can I spend on a hotel?
The maximum rate that’ll be reimbursed within Germany is (as of May 2019) 70€/night. For trips outside of Germany there are different rates which you can look up on the internet, for example here. If you book a more expensive hotel, you have to justify this. However, we are a public institution, spending tax payer's money, therefore you may only book the cheapest agreeable option.