Two more such places come slipping out of the imagination. Hinting, but not actually establishing that they can be useful plot twists.
The place jam-packed to the gills with unusual things and curios and objects would probably be more obviously useful. I've already established that they will need to get something. (But not everything. One thing they will have to do something more dangerous.)
The other place is just plain fun. An odd little building with peculiar architecture. . .
Maybe a waystation. Even to get to the other place, since its caretaker is so odd that they push their luck just showing up, still more by wanting to take something away.
