Baden-Baden has more than 5000 hotel beds and November is low season.
If you book early, you can find accomodation for less than 70€ per night.
In booking web sites choose "less than 3 km distance from center" to be in
walking distance from the conference site "Kongresshaus".
booking.com search for 5 nights
Make sure to mention that your travel for work to avoid the city tourist tax of 3.80€ per night.
