A: To estimate your bankroll requirements, use this rule of thumb: (For this calculation winnings are not taken into consideration.) Six spins a minute means 360 spins per hour. If you do not replay your winnings, for each hour of play you would need 720 coins for two-coin play. So, per hour, your bankroll requirement is $18 for nickel machines or $90 for quarter machines, if you play one coin per spin.