I would look at how they basically maintain minimal tables of payments which can be used to pay for service. Taler is more complex to handle being a 3rd party d

I would look at how they basically maintain minimal tables of payments which can be used to pay for service. Taler is more complex to handle being a 3rd party doing this, but Mullvad seems to do a similar idea of separating payment from the account itself to allow for anonymous payment.