Prepayment towards goods they will purchase in the future

[jackiemenasco]

I have customers wanting to make a prepayment towards goods they will purchase in the future. 

For example: We sale animal feed & supplies. I have customers who want to pay $1000 towards their account, and then just come in and get things as they need them. How do I do that?

[Minion]

What type of Square hardware are you using?  A gift card for credit is the only thing that makes sense off the top of my  head.