Thanks for reaching out to the Community, DG96.
I'm here to provide you some insights about the difference between the two transactions. In QuickBooks, you'll enter Expense transaction at the time of purchase for goods or services that have already been paid. On the other hand, if you purchase and want to pay it later, then you'll enter the transaction as Bill.
The first and second bullets are correct. The third bullet, you can create recurring for "both" expense and bill transactions. Fourth, expense and bills contain "Item Details". Lastly, you can add Attachments to expense and bill transactions.
I've added some links you can refer to learn more information:
Please let me know if you have any other concerns. I'm always here to help.
