I think your comment would have been more insightful if you had at least pretended to try to account for labor before saying "They charged me 4000x the cost of goods!".

To be clear I'm not even asking for you to account for the cost of your printer, the 3d scanner, and software licenses in your math. Let's assume that all those are free. How many hours of specialized human time was spent on consultations, scans, design, reviews, to produce working guards for you?

The next question is then, of course, how much do they charge for subsequent guards now that the scan has been done and validated? Is it still 4000x the cost of raw resin?

I did qualify multiple times that there are costs associated with engineering, So I feel that it it's implied that the 4000x figure is a naive one.

I'm sure labor is involved, and maybe it's a lot, but it still seems like an awful lot of money for a piece of plastic.

Even if the actual specialist labor had been minimal, there's also the amount of time and effort it takes to accumulate enough knowledge to become a specialist. It's like the joke about spending $200 for a repair guy to come kick your printer in just the right spot to fix a print jam--you pay him $50 for kicking it, and $150 for knowing where to kick it :)

Yes, they will charge a similar amount for producing another guard from an existing scan - I’ve had that done. It was also completely unnecessary in my case, it’s clearly an easy money grab for some offices.