I have customers with a regular order flow (order, quote, invoice + fulfilment). These orders all go through SAP.
I also have customers who prepay a lump sum as a credit balance and place orders against that credit balance. Only the initial lump sum is recorded in SAP and I use a bunch of spreadsheets to track what they order and how much credit they each have left.
I'm looking for software to replace my bunch of spreadsheets. I know my current system is not good but I don't want to create anything custom before I confirm there is nothing else out there. Ideally it should be web-based SaaS and any price will be cheaper than building something custom.