Here are some actual sales figures:

http://feinternational.com/buy-a-website/#tabs-3

http://www.webrokr.com/soldsites.php

For sites/apps with steady traffic & earnings, the general rule of thumb for calculating valuation has been multiples of monthly net profit:

* 2002-2004: 3 to 6 x monthly net

* 2005-2012: 10 x monthly net

* 2012-2014: 20 x monthly net

* 2014: 30 x monthly net

So to flip a site for > $200k, you need to be doing approx > $7k/month.