Help/Advice: AR customized product with deposit or down payment

Hi,

so I have a model where I can customize cups/bags for customers. Once customized it will be reoccurring charges. Question is what app currently or can be developed where I can do this.

Scenario:

minimum deposit. 50 cases $30 each for total of $1500.
I would take maybe 30% of that to hold and customer will continue to buy or maybe even be subscribed to the retail price of $30.

so basically if customer wants to customized I’ll hold 30% they keep paying for retail pricing until they want to stop and finish whatever inventory I have in stock. Then I refund the deposit.

please suggest any other ideas you have that would benefit me and buyer.