Private plates £££

[the seeker]

HI ive just recently decided to sell my car which has private plates on. the other night i thought id run them through a plate valuation site, well actually two of them. The first came back with an offer of £700 and that would be the final figure i would recieve all the sellers fees and leg work would be done by there website. I also entered my details on another site same deal these guys took alittle longer to get back to me but when they did they came back with a figure of £1750. can anyone give me some advice as to the sale of private plates of shed some light on up to vales of plates in general so i can get a rough idear of what the true value is? any info on private plate sales would be good to cheers are the values going up or down ?