The DVLA issued new guidelines as of 21st October for what is required to register your conversion as a motor caravan, it seems to be more focused on the external stuff. From reading the guidance what they want is something that easily recognisable as a camper van rather than just a van with windows.
Here's the important bits
Motor caravan external permanent features
This list describes the external features which are commonly seen in motor caravans, and it is intended to provide guidance on what DVLA expects to see when considering your application:
2 or more windows on at least one side of the main body (this does not include windows on the driver or passenger doors) to provide a reasonable amount of daylight into the living accommodation
a separate door which provides access to the living accommodation of the vehicle (this excludes the driver and passenger doors); a window on this door counts as a separate window on the main body
motor caravan-style graphics on both sides of the vehicle
an awning bar attached to either side of the vehicle
a high-top roof (this does not include a pop-top elevating roof)
DVLA will need photographic evidence of the completed conversion.
Internally the guidelines are pretty similar to what they were previously except they state minimum of 1 hob ring
For a vehicle to be recognised as being converted to a motor caravan it must meet all 4 categories shown below. For DVLA to change the body type, the vehicle must have the external permanent features described in the DVLA guidance for converting a vehicle into a motor caravan.
Category 1: Seats and table (1 example for both)
The seats and table must have the following features:
they shall be an integral part of the vehicle living accommodation area, mounted independently of other items
a table mounting arrangement shall be secured as a permanent feature, although the table top may be detachable
permanently secured seating must be fixed to the floor or sidewall and available for use at the table
Category 2: Sleeping accommodation
The sleeping accommodation:
shall be an integral part of the vehicle living accommodation area
can be either beds, or beds converted from seats
must be secured as a permanent feature, either with the base structure of the vehicle floor or to the side wall, unless the sleeping accommodation is provided over the driver’s cab compartment
Category 3: Cooking facilities
Your conversion must have a minimum of a single ring cooking facility or microwave, which shall be secured directly to the vehicle floor or side wall as a permanent feature.
If the cooking facility is fuelled by an on-board gas supply:
the fuel reservoir must be secured in a storage cupboard or the reservoir secured to the vehicle structure
If the cooking facility is fuelled by gas having a remote fuel supply:
the fuel supply pipe must be permanently secured to the vehicle structure
Category 4: Storage facilities
The storage facilities:
can be a cupboard or locker
form an integral part of the vehicle living accommodation, mounted independently of other items, unless incorporated below the seat, sleeping accommodation or cooker
must be secured permanently to the vehicle floor or side wall except when the storage facility is over the driver’s cab compartment
All the info can be found here
https://www.gov.uk/government/publicati ... or-caravan