No it is a registry office and a museum, but not a hotel!
You can park directly in front of the entrance at the Toscana parking lot ksotenlos and has a walking time of 5 minutes to the castles.
Castle maintenance fee:
You can go to the lake castle place and around for FREE, only when you go inside, then you pay the castle maintenance fee.
The entrance fee for the museum is payable directly at the entrance to the courtyard and is payable only if you go inside.