There is no magical formulae how much a typical website will cost. There are many factors and consideration that may affect the price of your website if you intend to sell it.

Such factor includes the number of visitors your website typically generated per month, total number of years of your website or domain name and etc.

There are one general method that you could use to know how much is the cost of your website.

You could get your website appraised. However, you need to get those respected Website Appraisers (e.g. www.buysellwebsite.com )

Note down the cost of your website and you could participate in various forums and invite the readers to bid for a higher price. Some of these popular forums are digitalpoint forum and sitepoint forum