Does anyone have a recommendation for a template for terms to attach to purchase orders?

Glad to have you here in the Community, @drax. 

I'll share some insights about the terms template. 

A Terms of Service Agreement is a set of regulations which your vendors must agree to follow in order to use your product/service. We're unable to recommend a terms template since this is particularly tailored depending on the type of your business. 

However, you'll need to manually create a template and save it for the following acceptable file types: 

•     PDF
•     JPEG
•     PNG
•     DOC
•     XLSX
•     CSV
•     TIFF
•     GIF
•     XML
   

Then, you can attach it to your purchase orders. Here are the steps: 

1.     Open the purchase order transaction. 
2.     From the bottom left, select Attachments.
3.     Browse and select the document you want to attach.
4.     Select Open, then Save and close.
    

Please see the screenshot below to show you the second step. 

For more information, you can check out this helpful article: Attachments in QuickBooks Online.

Stay in touch with me if you have any other questions about this concern. I'll be around to help. Have a great weekend!