Thanks for your replies!
Maybe you know of a better way to implement a paper trading (if a broker has no demo account)... or phantom trading is currently the best option?

It comes to a more general question about the strategy development process. What is a best practice? After a successful backtest start a live trading with small capital and slowly increase its amount? I was thinking about filling a gap between backtest and live trading with paper trading. Or it doesn't really help? What's your experience? Thank you!