There were semi-trailer units based on several Mercedes-Benz lorries. This semi-trailer unit is most probably an LZ 8000 which was offered beginning in 1933. It was based on the Mercedes-Benz type Lo 3500. It was a formerly vehicle of a Cologne haulage firm.
The vehicle had a special semi-trailer for furniture transport and a crew cab. For sure, these were changes according to customer’s request. The MAN D 1 in the background had a similar box body.