You can create and use only one account. If you accidentally created more than one account, please contact support to solve this issue.
Working with your account
Yes. You can have so many deposits as you wish.
For Perfect Money and Payeer, minimal withdrawal is 0.1 USD.
For cryptocurrencies: 0.0005BTC, 0.025ETH, 25XRP, 0.12LTC and 5USDT for Tether ERC20.