Ben - I sympathise with your point of view, and concur that displaying the flags would be a sensible idea.  My preference is to show them in the column area - and if I was only looking after the english speaking world I would suggest that the column heading be 'Flags' and the contents show A=aggregrate, Z=zero price and P=print.  If we use check boxes, then I suspect that the framework requires one per column and then if we use the heading Aggregate we end up with a wide column.

Note that the printed invoice layout may shuffle the order - we use Patient/Date/Product Type|Template/Product Name with aggregated template items coming first.

Hence our invoice preview is almost aways different from the invoice screen display.

Note also that the invoice print logic may over-ride the flags - ie I can set Print=No for an item in the template, but the invoice print logic will still print the item if its price is non-zero.

However, that aside, I agree that it would be useful to show the flags in some compact form.

Regards, Tim G