The car is being bought either as a demonstrator or as a fleet purchase at a fleet discount and, as such, has to remain in the keepership of the dealer or fleet for a stipulated period. Another broker was criminally prosecuted for not being upfront to a client about this type of pre-registration. At least this company has been honest with you. You need to check with your insurer because, on the insurance form that asks if you are the registered keeper, you will have to say 'no'.

Also any ANPR tickets the car gets will go via the registered keeper and could be delayed, invoking a penalty. Make it part of the contract that you get the V5C registered to you within the time they specify. There is a possibility that the arrangement may be illegal under Section 43C of the Vehicle Excise and Registration Act 1994, but I have not heard of this being tested in a Criminal Court,