When you buy the vehicle you will most certainly need the CG and ‘Certificat de Cession’ in the name of and signed by the previous owner to transfer the motor into your name.
If you do not have this you will almost certainly need to take the FFVE route for which you will need the CG in some form, even if one or two previous owners ago, plus a bill of sale clearly stating that the vehicle has been sold to you as is on such and such a date. I am certainly not an authority on FFVE matters but I know from friends that every case is taken on its own merits. Some applications can be smooth and others very tiresome but eventually they all seem to get through providing the vehicle has not been stolen, previously exported or written off etc.
Anyway, going back a stage…if you have the CG and cerfa form signed and dated by the previous owner you open a ‘Demarche’ on the ants.gouv.fr website. As well as these two papers you will also need a form of identification and a CT certificate. If you do not have the latter you can download the ‘Certificat d’identification’ which will allow the CT inspector to correctly identify the vehicle and control it accordingly. Whether the car passes or fails you can then submit this to complete the registration in your name. You can then get on with your renovation. If as is likely your renovation takes longer than the two months permitted for a contre visite then you will need to start the CT cycle again when ready but you will at least have fulfilled the statutory one month timescale to register the vehicle in your name as Stella mentioned above.
I bought the truck, arranged the insurance and drove it home. I have a CT booked for Thursday and the examiner I use said that the CG in the previous owners name was all he needed to test the car and the ‘Certificat d’identification’ was not required.
I know two people who have been stopped recently without CT and although it is of course usually a fineable offence (i believe about 135 euros) they were both cautioned and let off because the gendarmes were either in an extremely good mood or aware of the covid related backlog. As I said above I managed to get an appointment in two days, possibly because I take several of my cars there, but I know that there can presently be a wait of a couple of weeks or more in certain areas.
Incidentally there is a stage in the immatriculation process when they ask if you have the code for the cession. This is granted to the previous owner when he files his paperwork and records that he has sold the vehicle to you. He then passes said code to you. This is the route I have always taken previously but they do give an option if you do not have the code. I am expecting to receive said code tonight but if it is not forthcoming then I will have to enter ‘no’ and take the other route.
So where there is a will there is always a way and although I apologise for the long winded response I hope that my input and Stella’s advice has been of help.