Hello there ,
As i understand from reading your project description, you need to add a wallet system in your store Don't worry- I believe that I can be the best choice for you with this project.
Do you want to refund customer's amount to his/her wallet?
What is the transaction charge you want to apply ?
Do you want the customers to transfer wallet amount to other wallets ?
Do you want to send email for verify before transfer amont to other wallet?
I'm very interesting in this project and waiting for your reply.