Good evening, @donmoss.

Purchase orders (PO) are documents you send to your vendors to state your intent to buy a product/service, define the details of the purchases, and an agreement with them to receive product/services under the agreed-upon terms. This is why you can't customize them like Invoices. You can add attachments to them with a limit of 20MB which will allow you to add a picture of a logo. However, I know this feature could be helpful for you and others in the future, so I'm personally going to submit feedback to our Engineering Team. The feature can then be considered for future updates.

Feel free to comment below if you have any other questions. Best wishes!