Only two of the former cavalier houses - which are part of the palace ensemble - have survived. Built in the first quarter of the 18th century, it housed princely officials and later wealthy citizens, such as the Ruschka family, who had become wealthy as brickworks owners during the construction of the palace. The representative rooms were on the bel étage on the upper floor. In the 20th century, it was inhabited by the family of the Jewish citizen and merchant Leopold Wolf. Here, too, an unjustified expropriation took place during the Nazi dictatorship. In 1962, the Rastatt district acquired it. Since 2008, it has been owned by the city of Rastatt.
After extensive renovation work, the Rossi House has been open to the public again since July 2018 and, with its large, covered inner courtyard, is used as a citizens' forum for city events. It also houses the city's senior citizen work, the senior citizen's office, the Alliance for Families, the Inclusion Service Center and the office of the Rastatt Senior Citizens' Aid Association. The Schlackenwerth room will soon house a permanent exhibition. On the upper floor - the Beletage - there is a spacious wedding room available for those wishing to get married, where they can say "I do" in style in a magnificent, baroque setting against the backdrop of the Residenzschloss.