We currently have 2 actions and 3 triggers configured on Zapier.
https://zapier.com/zapbook/quickfile/
Zapier is great for triggering events in real time when something happens in QuickFile. Or conversely if you want to make something happen in QuickFile when some event occurs on another one of your apps.
If I understand this correctly what you’re trying to do is more of a reporting problem related to isolating those part-paid invoices and knocking it of your bank balance, I’m not sure Zapier will be a massive help.
Normally in accounting you’d use a balance sheet to determine a company’s NET worth, in your case I think it’s the cash position you’re seeking. Without some how tagging those deposits, I’m not sure how else they could be isolated.
Another option you’ve got is assigning a project tag to all part paid sales invoices and using the NET paid on the project overview screen as a possible way to get at that figure. Either way I don’t think there will be a unified report and it will likely involve comparing two separate reports, e.g. your bank balance and the project balance.