flippa is a cesspool of worthless sites, scams, and con-men.
But, there are some occasional transactions that are worth looking at, if only to get ideas of things to build.
Here's a recent sale of thecupcakeblog.com: https://flippa.com/2736282-over-1000-ad-rev-199k-visits-475k...
Those come along about once or twice a month.