It is pretty simplistic and a bit confusing to start - maybe add some text that you need to click on the money image to get money, that then disappears after first few clicks?
I would really recommend to round upgrade costs - currently they become non-integers after a first upgrade, so having the exact cash on hand is often not enough to buy it, which is confusing for the player.
If you lose, you restart with all upgrades you already acquired (this also includes earning money per second for the time you idled in the main menu, and keeping the already acquired score) - I assume it is a bug and the player was intended to start back with the clean slate.
When the tax is due, it removes all your money, not the tax amount - this feels a little bit weird. It also does not interact with the "Taxes Evaded" number, which is also weird.
The text buttons have a weird collision box, I needed to try clicking several times to activate them.