In the last few months I've built a little API and it turns out a few people and companies want to use, and I want to charge for, however I'm struggling to find a way to handle the accounts and billing side of it.I'm looking for a simple system that will handle the accounts side of it all - signups, quotas, billing, payments etc to let me focus on actually running and growing it.I have looked high and low and I simply cannot find anything that does API Account Management at a reasonable price point.Everything seems to overdone and corporate, IBM API management sort of things, costing thousands of dollars to even get started with!Alternatively, there are a few Open Source options for managing accounts and quotas which look ok, but as far as I can tell they have no ability to accept payments, integrate with Stripe/Braintree etc, issue invoices etc.The closest thing I can find is 3Scale, by RedHat, but even that costs hundreds of dollars to start out with (and it also doesn't look very good anyway). It's also hugely over complicated.I looked at MashApe/Kong too but that doesn't seem right either, you have to integrate with their market place, and their whole approach to authentication and quotas just feels "off".It's like what I'm looking for is almost like a Shopify or Stripe for APIs?! Just something that lets people sign up, handle accounts, billing, invoices, quotas etc and which is reasonably priced. I'm obviously willing to pay for it, but the huge corporate solutions aren't right and the GPL stuff doesn't have billing abilities.And obviously, while I could build it all myself, I have no interest in building an account management platform and integrating with payment gateways, handling invoices and so on.Is there a service I haven't found yet?I would love any insight about how others are doing this.