We recommend the following hotels. You need to make the reservation on your own, i.e. all contact (reservations, cancellations etc.) must be made directly with the hotel.
Since 2014 German hotels are obligated to pay City-Tax (5%) for all private guests. Therefore almost every reservation confirmation includes the City-Tax. Please mention at the registration desk, that this is a BUSINESS trip. Then you don't have to pay this tax.