There is even better guy - danarakvica, with 190 transactions totalling $338000...
They do some "magic tricks

" with chartboost, I believe it is all pure blackhat, and inexperienced user who buys their shitty game for $2k next day will be burned and banned for life from chartboost. One of those tricks is ad filtering, when you allow only most expensive casino or shooter game ads to show in your game, but chartboost will ban account for such filtering sooner or later.
There are lot of possibilites, as show ads outside the game, in random time, as it was described in another thread here.
In flippa there is even pure screenshot photoshoppers, who fake stats, and when I posted to flippa support, they didn't care about it, just some bla bla bla response after a day.
And in this time some dumb buyer bought that shitty app for $2000...
Don't believe those scammers, be very careful with those listings.