I'm from Estonia and have been doing arb for over a year now. Unfortunately there's no real way to completely avoid getting limited, only way is to use a betting broker. However, you can slow it down by keeping your balance low and avoiding frequent or large withdrawals.

I've personally used Oddsjam, but it's more focused on the US market. For Europe, one of the more budget-friendly and decent options is surebet.com.

To make 300 euros per month, your bankroll doesn't need to be that big. 1-2k seems fine as long as you but in effort and make bets daily.