Not heard of them, but these guys all work the same way - money upfront and then, whoops, sorry we can't sell your timeshare, or he pulled out at the last minute, or we've found a buyer who will give you a huge sum of money but we need just a little more up front first. As I am sure you know, Europe is awash with surplus timeshare so prices are very low (compared to what you bought at). I don't believe that there is any reason to pay anything upfront - they should be willing to work on a percentage the same as any other selling industry does (estate agents). Advice you to steer clear.