topr8 - 7:44 pm on Mar 25, 2012 (gmt 0)
NB. most contacts to purchase a website are just scammers. either they suggest you use a paid valuation service or they think your domain name is valuable but only want to offer a pittance for it.
IMHO, and doubtless others will disagree, the first thing to do in this situation is to ask them to make an offer... that is then the starting point of any negotiation.
only you can decide what the website is worth to you, based on how much you earn from it now and how much you will earn from it in the future and what you would do with the money that is paid to you for it.