Arrakis might be a lawless desert where you can stake a claim wherever you please, but you'll still need to pay taxes in . No, it's not fair, as it's not like there's even any public services on Arrakis, just bandits, shipwrecks, political tension, and lots of sand. But pay you must, or the emperor will send his hounds.
You're only given a passing explanation of how taxes work in Dune: Awakening, and it's not actually that helpful, so you're likely to unwittingly fail to pay your taxes while you figure it out. Don't worry, though, to keep your base safe, I'll go over how to pay your taxes to the empire and when.
How to pay your taxes in Dune: Awakening
You can pay your taxes by visiting an Imperial Tax Representative in Arrakeen or Harko Village, which you can travel to by paying 2,500 solaris for [[link]] a taxi at any tradepost or flying there using your own ornithopter. Speak to the officer, who'll be marked on your map, and simply select "I'd like to pay my taxes", where you can choose to either pay in full or just for a single sub-fief.
It's quick and simple to pay your taxes, which is handy as you'll need to do it regularly to avoid the consequences—the sardukar. However, keep in mind that if you're paying for a taxi to take you to either faction's stronghold each time it's due, rather than flying over there yourself, the cost quickly stacks up. I recommend getting an ornithopter of your own and flying to the edge of the map to access Arrakeen and Harko Village to save solaris in the long run.
You'll need to pay taxes on any sub-fiefs you have, meaning you'll end up paying quite a hefty chunk of solaris each cycle if you have two bases. You can check how much you owe and when it's due by interacting [[link]] with your sub-fief console—which I guarantee you've never looked at since your first placed it, so you'll likely discover that you owe the emperor quite a bit of coin, and [[link]] that it's already long overdue.