I'm sub'd for popcorn...
Whilst I don't like laughing at other peoples misfortune, as everyone can have trouble....
This though is like taking the list of things not to do & actually doing them....
Ever when I was way younger & got my first cars, I was never this naïve..
Cat D could be stolen recovered, damaged etc...freshly stolen more like reading what the OP has stated about the transaction...
£20,000 cash..really you got money to throw away that easy on a dodgy transaction...& how did you get the £20,000 cash out the bank as usually they ask questions for that amount.