It's what I call the 'Network' scam after the first one of the type I saw. They say 'no joining fee, only pay when you've had bookings', which sounds great. The problem is that they invent the bookings, always for next month, so they can take the money.
Paragon, who were the other bunch who caught trotski, came up with a variation which promised no joining or monthly fee, just commission, which sounds even better... until you discover that they wanted the commission for the first booking in advance 'so we can be sure we can trust you'. Obviously that's a fake booking too, but at that point they're waving a booking for the next few hours at you - ooooh! - so an annoying number of people fell for it.
It looks like they've switched to being a Network clone - their 'commission' has dropped, and they charge ?70 the second they invent a booking.