To pre-pay for upcoming services, first click on the "Receive Money" tab on the right hand navigation menu in the customer's profile.
Check the "Charge Multiple" box in the resulting dialogue box. Then select all of the invoices that they are pre-paying for.
Select the payment method and hit process payment.
If they are going to pay by credit card but you haven't entered it into the system yet, you will not be able to charge their card here. You will have to enter it into Pocomos first.
This will mark the invoices associated with the upcoming invoices as paid, so when the service is processed, there will be no need to collect any payment.
Another option to pay in advance is to change the billing option under the agreement settings
When adding a customer, you will then be able to select "Due at Signup" and put in the whole contract value. This will assign all of the cost to the initial job and the recurring jobs will be $0. If the customer has a card on file and it's on auto pay, the system will attempt to charge the card when you sign up the customer. If they aren't on autopay, it will mark the invoice as due for the full amount.