How were the Kaminoans paid for the clones? I mean, is that shown somewhere?

We know who ordered them, sure. And we know who really ordered them, by proxy.

But…

Who the hell paid for all of this?? And how did nobody notice??!

When Obi-Wan saunters over to Kamino there are 200 000 units ready, with a million more on the way. It doesn‘t make sense for a galaxy wide war to only have 200 000 soldiers in an army, so a ‚unit‘ was probably not one clone. But for the sake of simplicity, let‘s say that there are 200 000 soldiers ready to be shipped, and a million that are being raised/trained.

It‘s probable that the future GAR is clogging up all of Kamino‘s clone buisness with all those soldiers. They are filling all of Tipoca City, after all. Sure, there could be other cities where other people could be cloned but how do you keep your army of Mando-adjacents secret like that?

So, the Kaminoans proably priced the Fett clones higher than they would have normally because turning away all other customers doesn‘t make for a good reputation, and I think they would want to be compensated for that.

They also had to house and feed those clones for about ten years. And the ones training them. That‘s another thing Palps would have to pay for. Again, clones are clogging up all of Tipoca.

The food for the clones. You have to import a crap ton of food for that many clones, which would be expenses from hell in and of itself. And there‘s secrecy around it. You can‘t just contract 100 people to deliver all you need. You want as few people as possible landing on the planet that houses a secret clone army. So you need a contractor who can bring huge amounts of food. Regularily. And you also have to probably pay them a large sum on the side so they don‘t go blabber about it. Also, they will probably demand even more credits so they can themselves pay the people they get their wares from to not ask why the hell they need that much food.

And then there‘s the equipment. You have to buy loads and loads of equipment if you want your secret army to be effective. They all need armor, weapons, ships, all that stuff. And again, you have to mass-buy all of that. And it has to stay a secret. So they have to find a contractor for that, as well, and pay them big time.

Finally, storing the ‚finished‘ clones. That takes up space and energy and resources, as well. Just because they‘re ready for battle doesn‘t mean they don‘t cost, anymore.