Hi Lee Sommerfeldt,
I see you are in a inter-site flow but not inter-company flow (same company linked to the supplier site and customer site). 
In that case, I don't understand why you worry about the price. Price in inter-site are not used! There are no invoicing process (no margin, no profit) and the stock value received will be based on the stock value issued on the supplier site. So if using average cost, the AVC at the time of the delivery validation will be used as order price to value the stock received on the other site disregarding the price set in the purchase and sales orders.

I hope this helps.

Hi Lee Sommerfeldt,
I see you are in a inter-site flow but not inter-company flow (same company linked to the supplier site and customer site). 
In that case, I don't understand why you worry about the price. Price in inter-site are not used! There are no invoicing process (no margin, no profit) and the stock value received will be based on the stock value issued on the supplier site. So if using average cost, the AVC at the time of the delivery validation will be used as order price to value the stock received on the other site disregarding the price set in the purchase and sales orders.

I hope this helps.

Else you can use the action menu on the PO line to understand where the default price came from:

Hi Julien,

Thank you for your response. We'd like to avoid having the price included as it can otherwise appear in our reporting of Sales Order data. For example, the PMD order site in the image I attached is treated as its own BP, so I believe it would be intercompany. I've used the Price Explanation function which just tells me "Default Price" as the reason. This brings me back to my original question of "where is this price coming from?" We've encountered another item where not only does the price fill in, it is the incorrect price. There is no Purchasing Price List set up for these items. 

To retreive where the price come from:
1/Check if you have a valid price list for this product.

2/If you have multiple ones, then look for the price list associated to the reason code Default (usually this is the code 2).

3/If no price matches - I guess because not applicable to inter-site -, then check the base price set on the product:

4/Last, the system allows to use the standard cost as default price (parameter value PURPRICE)
So check of the amount matches the standard cost valid at the time of the PO creation.

Thank you Julien. This was it!