Cheers, thank for the notes.
In my case, it appears that a "friend" used the landy and they fell out. He broke the chassis and probably sold it for scrap. She did not believe him and registered it stolen. The garage bought it and I bought it. The garage has offered a full refund, however I'd like to find out if the "stolen" charge is changed or ownership is proved. If it does, I could get it back.
I have a feeling it going to get ugly and it's going to take a long time to resolve, if at all.
I did register it with the DVLA who then sent me a V5 and that triggered the visit from Plod. I have a V5 and a sales receipt.