Cheap new car purchase via the internet

Billridley

I have been researching buying a new car on the internet. It is significantly cheaper than buying from a dealer (in my case for a Mondeo almost £3500). There is a catch. The dealer pre-registers the car (so you are the second owner) and does not release the V5 registration document in your name for almost 6 months. This is because they are bypassing dealership rules and obtaining the car from the manufacturer on a fleet basis. Your local dealer cannot compete with this.
Retaining the reg document is not quite legal but they do it anyway.

My question I would like to ask is that if I purchase via one of these suppliers, can I then apply directly to the DVLA for a new V5 reg document with myself as the second registered owner (I think the form is V62.

The car not being registered in my name is worrying because will it invalidate any insurance claim or warranty, what if I have to produce docs to the police, what if I want to take the car abroad (you are supposed to carry the reg with you).

Can anyone advise please