You have been offered to test very good route at very good price. The test was successful, but prepay is required. The negotiations ended with the agreement signing, then you transfer the prepay and nothing happens or you get the route, that is beyond any comparison with the tested one. Next moment under any pretext you have been quoted the higher price consequently you are willing to send the traffic even to your own damage to prevent the biggest loss as you realize that it is the only way to get the part of your transferred money back. This is the way the providers themselves bring down the market forced by the desire to recover their “discounted” money by selling the routes at unprofitable price. But nevertheless it is better than to loose all the prepaid money that is more probably. That is why the prepay is worth be made to only companies that can send you their annual report approved by the auditor (almost all European tax offices state their reports on the web sites available thus making it available). So prepaying the unknown companies what don’t give any trade references and try to seduce you with the price and good testing results appear to be very risky.