For cricket this year, we engaged a company / app called "Team Pay".. they use it for social basketball etc.
It's been very successful at cricket, i'll be trying it at football this season - essentially players setup, add card details and each game they play they're charged an amount you've set up e.g. $10.
Just need a "captain" to go in and select the players on the app and then charge for the game.
In the dashboard you can set up specific amounts i.e. $5 for U18s, so i'm hoping this year I can just work out how much players owe on their subs and then divide by games in the season and set their amount at that.
We have setup for rego this year options for players to pay 25%, 50%, 75% or 100% of their fees when registering, and if 100% then offered a discount.
See how it goes i guess.