This is one I'm particularly proud of. Makes for a really fun magnetic fidget.

https://www.printables.com/model/1145644-geometric-shapes-with-embedded-magnets-for-constru

I train and deploy search and rescue dogs.

Somewhat, yes. The design I copied from uses 5mm magnets, which actually are pretty difficult to source, and much more expensive than disc magnets.

I'm curious if regular disc magnets would work as well, but you also need so many of them. Even the smallest set of 12 pentagons takes 60 magnets.

Though you also could do embedded magnets if you used discs....

Prusa Mk4s, but probably any modern printer could do it. It just has to be high enough quality so the small magnet balls can rotate so they can self-align and click together.

It's just like any skill. If you were a professional football player, you'd still run fundamental drills every practice. Same with dogs.

You have to keep their strength and cardio up, so they can work for long periods of time. You have to keep their motivation up so they want to work, and you have to keep their skills up so they can do the work without thinking about it.

A well trained dog doesn't understand that it's a "job." A dog is just out there having fun and doing their best to get a reward at the end. If you're doing it right, your dog wants to work more than anything else in the world.

Yes. I trained dogs before, but only personal dogs, not professionally. I got lucky that my prior training techniques were very similar to the industry standard, so it was a relatively easy transition.

We probably run about 50 training scenarios for every 1 deployment per dog.

Ideally you'd be training from a 3 month old puppy until they are 18 months before they can test, which would include at least a couple training scenarios a week from in that window, so you'd probably have 150+ training scenarios before you even test. Additionally you would be doing daily behavioral training, similar to what you'd do if you want a very well behaved pet.

After they are certified, you'd still run 1-2 scenarios a week, 3-5 day seminars a few times a year, plus other related cross training if you want a high level dog.

Every region across the world has it's own standard of what they consider a deploy-able dog. Some are highly paid, expert dog trainers that deploy in extreme situations. Some are casual retired bored rich people that want to take fluffy to something exciting, and just show up to random emergencies saying they can help, and have no actual formal training.
Most are highly dedicated volunteers that spend an extreme amount of time and money to ensure they meet the highest standards just in case they are called on to help out with people's worst days.