Tips to manage subscription payments (for an unlimited copywriting service)

I'm looking for a low-cost and simple solution to manage recurring invoices and subscription payments for my unlimited copywriting service Scribly.io.

Currently I'm relying on manually generating and chasing invoices. I'd love to find an automated solution that doesn't break the bank. I've heard that invoiced.com could be a good solution - does anyone have any ideas/tips/ thoughts?

The website is built in Webflow, but I'm thinking of hosting the payment page on a sub-domain so that I don't have to pay for any other third parties to integrate it into Webflow (I sound like I know what I'm talking about, but that's pretty much the extent of my implementation knowledge 😁)

Also, feedback on Scribly.io would be most welcome! It's my first ever solo thang ✌️🚀 .