Ultrakill pricing and help with tax

[Gr3nd3l_Ma1n]

Heyo, I’m looking to buy ultrakill, and I have 2 questions.
1. The game is currently $24.99, but when I put it in my cart the price turned into $18.74 (Not that I’m complaining lol), just wanted to know what’s the cause of this?
2. Is this $18.74 price including sales tax or no? I’m gonna get a gift card with $18.74 in it and I’m scared they may charge more and render my card useless.
I’m new to buying stuff on steam

[K-Driver]

The game is currently on sale for 25% off.

American store price does not include the tax and adds it on top of it.

[blunus]

1. The game is currently on sale for 25% off and that's $18.74. The base price is $24.99.
2. In the USA, the price does not include tax and you only see that at checkout. The EU requires that the tax be included in the price tag.

[Gr3nd3l_Ma1n]

Ah ok thanks. Also: Hakita mentioned something about increasing the price when he adds more content. Exactly how much is that increase?