Field help:
Have you incurred any overnight accommodation costs?
If you had overnight expenses in connection with your off-site work, select "yes". Overnight expenses include, for example, expenses for
- a hotel
- a guest house or
- a flat that you have rented temporarily.
You should be able to prove all expenses to the tax office, if necessary.
Accommodation costs can only be recognised as income-related expenses in the amount actually incurred, but for a maximum of 48 months at one and the same place of work in Germany, and after that up to a maximum of 1.000 Euro per month.