I had my computer running for many days to mine bitcoin with MULTIMINER. When I reached 0.017 I tried to make a withdraw. A message said I had to pay a maintenance fee of 0.0005 or pay to upgrade from free to a paid contract to be able to make a withdraw. I am new to Bitcoin mining and buying so I decided to play it safe and just pay the 0.0005 to see how it turns out. Once I made the payment I sent them a message asking when I can make a withdraw. I never received a response so I sent two more and no response from those either. I just tried to make a withdraw again and it says I haven't paid any maintenance fee. I also noticed the address to sent the payments changed. Those idiots scam people. They get you to give them a little or a lot and then they ghost you. I wanted people to know my experience so people don't make the mistake I did.