How long until these items expire? I really want to get all three of them, but it's going to take a while.

All three items came out very recently so I think it will be a number of months before they retire.

Specifically, the Dark Mountain Statue came out in June, the new Vanity items came out at the end of August, and the Trapped Fog came out just this week. I really don't think you have to worry about them retiring anytime soon.

Plus, staff usually makes a news post when cash shop items are about to retire so you do have a few weeks' warning whenever they do retire.

Thank you for your answer! It's much appreciated.

I understand, I also don't buy CSC and rely on the Bathhouse/buying gift cards with sP. The items may actually be on sale for Black Friday so I would wait and see if you can buy them then :D

Oh my gosh, I never remember that Black Friday is a thing, thank you for the heads-up!

You're welcome! I hope you can grab everything you need :)

It'll be a while, but that said, keep in mind - Subeta usually does a Black Friday sale too.