You can request a valuation from www.nationalnumbers.co.uk and if you are unhappy with the value they put on it you can request a higher price if you decide to advertise it on their website.
hi, you may find out ,as i did, that the numberplate companies will not buy your cherished plate. what they tried to do for me was to advertise it on their site as tho' it was theirs and if they get a buyer, they will contact you and offer to sell it for a commission. They are very reluctant to actually buy a number because they can stay on their books for years.