V5 document

The original is needed and should be in the car but take a coy and keep it in the caravan.  The police do spot checks of documents.   The MOT certificate also has to be taken if appropriate.

We keep the original in the car.   We also have a copy in the caravan, and then we have scanned copies available on our computer - and in our email inbox.

You should also keep your passport (or other identity document) with you.  You can be asked to produce them 'on the spot'.  In thirty-seven years of driving in France (every year) we have never once been stopped but you should keep them with you, just in case.

Just for information the V5 isn't proof of ownership.

No it states the registered keeper. 😉

We also have scanned copies of all our important documents, held in a Word document (password protected) held up in the cloud.

Passport, insurance docs - house/travel/vehicle, vehicle docs, file with telephone numbers - banks/credit cards/breakdown cover.

Wing if you are concerned about theft buy a floor safe box about the size of your passport and put it in a hidden location you could also if you have space hide one in your car, at the very least lock your documents in the glove box