Invoices for add-ons only show a total amount for each service, but multiple customers are represented. For a product like Acronis, it's very difficult to break down the total and know what should be billed to each of my customers. Going to the Acronis portal and viewing usage is possible, but there's no historical data to support the usage in comparison to the Atera bill date unless you look at it at the exact moment that Atera's bill is created.

I have other services with other providers like Pax8. They are a bit more expensive for Acronis, but they break everything down by customer for me - saves loads of time when doing my monthly billing. It's a hassle to move everything, but I may do it just to get this feature. It's that important to me.