The In Tray functionality for purchases was a great addition and is extremely useful.
I'd like to suggest being able to attach the invoice to a Purchase directly from the Edit Purchase window.
Currently, if I'm editing a purchase and notice that no invoice has been attached, I can't just click an "Upload File" button. I need to exit the purchase, go to In Tray, Add Document, Link to Existing Bill, find the original Purchase I was working on and then link the uploaded document.
It would be extremely useful to avoid all of these extra steps and just have a one-click upload feature, similar to the Unlink button you already provide in the Edit Purchase window.
