You can open accounts in US Dollar, Euro and Japanese Yen in MetaTrader 4 and NetTradeX platforms.
You cannot change the denomination of your account, but you can open another account denominated in a different currency. Then you can simply transfer funds from your old account to your new one.
You can have as many accounts as you wish.
On the part of IFC Markets there is no fixed minimum replenishment amount. Minimum size of account replenishment depends on the selected method (billing system).