[HarryM]

13 sites probably isn't enough to base your decision on. Speaking for myself I always have at least 1 sale per site, but it can be 6 months later. You need more time to get listed, build more sites, make some hubs and test different sponsors.

Sometimes people I know ask how to get into this business, I tell them to just forget about the idea unless they have enough money to start things off properly with and can survive the first months/years of crap all money coming in. Can't really expect instant returns without laying out a shitload of cash first, same thing goes with any business really...