This is how you do it: (I built exactly what you want)

- Build a bank

- Become a visa/mastercard issuer or create your own payment stack (which will have 0 merchants)

How to build a bank (checking, no savings):

- go to central bank website, you should be able to find the offices where you can apply for that license, call them and ask for law firms that already do that

- it costs a few hundred thousand of dollars - fees and lawyer expenses

Now the hard part: To become a bank (the type you want) you need a lot of money. 4 years ago it would take around 24mi to do that in the US. That money is usually retained by the central bank. After having that retained you need to retain at least 15% of all checking money in the central bank account, which makes it even harder to get started.

Summarizing: get 30 million, call CB, the lawyer.

Now, the Pro-Tip: A lot of banks can act like a proxy. You create your firm and reach an agreement with an existing bank to operate under it's license and structure. simple.com is just that :D