If he wants to just buy a car outright, then he does not need a licence. If finance is involved then yes he does need a licence.
See extract from the AutoTrader's Site.
"Maybe you are an individual under the age of 18 or maybe you have relied on public transport so long that you never obtained a driver's licence. Now a vehicle has come along and you don't want to give up the opportunity of owning that specific model. Are wondering if you can legally own a vehicle even though you are not a licensed driver?
Unlicensed driver
In short, yes, you don’t need a valid driver’s licence to buy a new or used car from AutoTrader. It is not like buying a television set, where you must produce a licence to buy one. Not having a driver’s licence means you can own a car but not drive it on public roads yourself. You will need a licensed individual to drive the vehicle back to your home or arrange transport for the vehicle.
However, if you are planning on financing the vehicle, you will require a valid driver's licence. This is because lending institutions will require the vehicle to be insured for the entire financing period to ensure that they will be able to get their money back if anything happened to the vehicle. But if you are purchasing the vehicle with your personal savings, you will have no problem at the dealership."