Comment by MountBridge

I'm not looking at developing any solution. Rather, I am ready to choose a system that will optimize at least this basic part of the work with invoices, their formation and sending. How to choose is another question. For example here (https://inai.io/) in general no-code, and it turns out to be possible, but I suppose such system will be much less enable to customization) In addition, a system must allow you easily migrate off with all the data.