Transfering USD to Moscow

Hi folks,
This is Dani, and expat here in Moscow.
I'd like to know if there is a preferable way to transfer 20k+ USD to Moscow, to then convert them to RUB.
I have a card account in Sberbank in Rubs and I think there is a way to open another one in USD.
What I don't know which account or bank will ask me for the least commission. I heared about 1% commision or that the money in dollars could be frozen from 1 to 2 months.
Is there anybody who knows a bit about it?
I will really appreciate any help
Cheers.
Daniel