There are a few ways to lessen the number of payments you make to Pirate Ship, which can make your accounting easier:
1) Set a Default Payment Amount
Set a Default Payment Amount in Settings / Payment Method. This means that if you don't have enough credit in your Pirate Ship account balance to purchase a label and have to make a payment, you will add this amount to your account.
So for example, say you have $0 in your Pirate Ship account balance and you’re purchasing a label that costs $5.
If your Default Payment Amount is set to "No Default", you will only be charged $5, and you'll have no credit left in your Pirate Ship account balance after the transaction.
But if your Default Payment Amount is set to $20, you'll be charged $20, $5 will be used for purchasing the label, and you'll have $15 left in your Pirate Ship account balance for future use.
2) Adjust the Total Charge amount when creating a label
When you're creating a label, right before you click the BUY button you can click the Show Account Balance & Total Charge link at the bottom left to show more information about how you're paying for that label:
There you can edit the Total Charge field. Set it to whatever amount you'd like to pay. Any credit that isn't used by the current label purchase will be left over in your account balance:
3) Add credit on the Reports page:
You can add credit using a debit/credit card or through a PayPal account here: