You're second question -if I'm understanding it correctly - does, in fact, bring up the question of the competition's fee structures. If my desired "costs-plus" fee is prohibitively expensive vis-a-vis the competition, than I won't sell very many widgets, if any. For the vast majority of us - we can't develop our pricing in a vacuum.
What I am saying is if you can not produce a product and hit your target profit margin than you need to look for alternatives. Not every lab can be competitive and if so you should not be offering this service. This is the part that most do not understand. If you get a hawley retainer in your fixed lab and it takes you 3 hours to bend the crib, why would you ever offer that appliance? Specialize in the products you can do EFFECTIVELY and different than your competition and your fees can be justified. If you are marketing to the broadest demographic and not doing something substantially different than your competition how can you justify a higher fee?
Also, I'm confused by your statement about the invoicing of multiple units. I get alternative treatment plans with varying fees based on the type of restorations chosen. Are you saying you actually provide dummy invoices for each alternative not chosen, as well as a real invoice for the selected path? That seems onerous to me given I've had discussions with accounts who have trouble deciding between eMax, eMax Multi, layered eMax, PFZ and a microlayered FCZ...
I send an invoice with different modalities, screw retained, cement retained on custom abutments, and cement retained on stock parts. I have macros set up to allow fast invoicing. Confusing or not it allows the client to make the dollar amount choice and makes me look like a hero offering alternatives rather than the money grubbing lab looking to screw the client. As discussed in a prior thread we also send a form letter to have the client sigh to streamline some of this as it relates to brand specific parts verses 3rd party parts as well.