We use a software called Dext which seamlessly integrates with Xero for expense management. The beauty of Dext is that capturing invoices can be reduced to simply forwarding an email, attachment, or picture to an email address for your own account. So for example, if you have a regular supplier, you can simply set up an auto-forwarding rule to automate capturing the invoices for purchasing inventory. For arbitrage sellers, you can use their app to capture expenses by just taking a picture in-app.
We choose Dext because it currently offers the highest fidelity for reading expenses based on its machine learning OCR engine, which lets us be a lot more efficient.