Personally I would drive down to do the deal on the day it's being collected, but then again I have had some relatively long disappointing trips to not collect cars.
If you have to do it remotely, I'd ask for a photo of the front page of the v5 and a photo of the drivers license of the guy selling it. Recently my NatWest and Halifax banking apps have both implemented a feature where they check the account holder's name against the AC number and sort code. If all three of those don't match up, I'd be asking questions / walking away.
So what is the going rate on a beetle these days anyway?
Yep. This was my approach to car buying. These days I usually buy unseen but from a dealer. If the car proves to be a 'bag of shit' I will always make their lives unbearable if they don't take it back or give me a refund.
Of course, with a private sale, your options on returning the car are more limited.