[Closed] Another van conversion Q. Advice please

Im after converting a LWB sprinter or crafter. This will be my camping(+mtb)/work van and was wondering if there are do's and dont's regarding change of use to camper ( poss cheaper tax or insurance ) and if its registeted as a camper can i still use it for work (building/carpentry)? What are the requirements for a camper.. a bed & sink?
Are there any problems insurance wise if the bulkhead's removed? Do you need seatbelts in the back?