Referencing a cell as the Value to use in an IFS statement in Google Sheets

I'm using an IFS statement to decide what a cell should use as a value dependant on what is entered into the cell. Which is fine, except that I have to hard code it into every cell that uses it as an equation. I need to have the Value1, Value2 etc be whatever is in another cell. That way I can update one cell and have it cascade.

=IFS(C34=<100, "$10", C34=500, "$5", C34=1000, "$2") I need the "$10" to be a value of another cell, ie B28

I've tried !B28 , $B28, =(B28) and every other thing I could think of. I can't find anything online in Googles documentation.