When a purchase invoice is handled for acquisition, appreciation or maintenance on a Fixed Asset, the FA Posting Type field can be filled in to choose which of these 3 types the invoice concerns.
However, it is not possible to fill this in on a purchase order beforehand: there the field is unavailable to add to the lines.

This has risk to errors, because when a purchase order is created first (as most companies do to monitor purchases and costs), and then in the purchase invoice the user selects the order lines or receipt lines, the FA Posting Type will be acquisition by default as this is the first option.

Please make it possible to add and fill in the FA Posting Type field in purchase order lines.