This Insurance stuff depends on how you interpret each Companies wording
Here is my take on it, and believe me there are other's who will have other views/opinions so my view is not necessarily the correct one.
Situation of an Individual:
They no longer own a UK residential property and live in a Motorhome and am not on the Electoral Role. They do have a family member or friend who lets them use their address as a 'Contact Address' for Mail, Banking purposes, Registration of Vehicles, Insurances, Credit/Debit Cards etc.
Insurance Requirements:
Some Insurers require you to be on the Electoral Role, some may not. All Insurers will expect the applicant to make full declarations about the vehicle (Age, Value etc.) plus the applicants driving history, length of time you have held a UK licence, Driving Convictions, Previous rejections for vehicle Insurance, Disabilities, Security devices fitted to vehicle,
Purpose of use of vehicle, where vehicle will be stored when not in use.
Most Insurers still look at Caravans and Motorhomes (this term includes all types e.g. Camper Vans, RV's, Fifth Wheelers etc.) as temporary use vehicles, to take occasional holidays in throughout the year and not as fulltime residential vehicles. Therefore, it is up to the applicant to disclose all 'Material Facts' relevant to the vehicle to be insured e.g. To be used to both travel in and be used as a place to live in as main residence.
Note that the question as to whether you will be travelling outside of the U.K. Is a separate issue at this stage, that comes as an extra requirement and permitted lengths of use outside of the UK may vary between Insurers, some allow 90 days, some 8 months whilst others offer 365 days European Cover, but that is, as I interpret the requirements for obtaining Insurance on a Motorhome, totally separate to the declaration of material facts about the 'Purpose of Use'.
If an Individual declares that they are fulltiming, the Insurers will accept that they may not be on the Electoral Role, however the Insurance premium will be higher than that for an individual who only uses the vehicle periodically (e.g. for holidays)
Some individuals may be able to register on the Electoral Role, albeit they do not reside at the address used for the purpose of registering and therefore, in order to obtain a cheaper rate of premium do not declare the material fact that they are living in the vehicle on a permanent basis.
Does it matter ?
That is solely up to each and every individual to make their own decision
