But though how many do actually ask for that when you buy online?
If the plates are going to be for road use, then by law they have to see original docs before they can issue the plate.
The ONLY legal get out for purchasing number plates without ID is to sign a declaration stating they are for show use/off road use only.
If the seller is across the border i.e Scotland their law regarding plates is different.They do not require proof of ownership or any ID to buy plates.
Remember in this country England,Wales it is illegal to sell plates without ID and doc's but not illegal to buy without.County flags and euroland stars were made legal to display this summer.
Regarding BS kite marks since last year, a mot station can not fail a car for not having the marks on the plates due to over 20,000 cars failing because of un-marked plates in 2 years.The law stating all plates must have the BS kite mark will be again reinstituted from July 2010 but this may changed due to EU legation.