If you want to participate in this event, I need to calculate a fee for you: withdrawing U requires a fee of 1 U, withdrawing ETH requires 0.45, the authorization fee is 1.6, converting USDT to USR requires a fee of 1 U, exchanging USR for WSTUSR requires 0.45, exchanging WSTUSR for USDT requires 2 U (go next door for a cheaper rate), and if you see someone saying the fee is 1 U, just scold them. The total fee is around 5 U.