Washington Hospital in the Bay Area charged me $2,010 for a COVID test when I went to their ER. Later I was told I was stupid for having gone to the ER to do the test there. I just never suspected they would charge that much.
Here in my municipality in Norway the media keeps repeating how/where/when to get tested, and if anything important changes the municipality will literally send a SMS to all its citizens to ensure as many as possible are up to date.
From my admittedly limited experience with the US (NYC/tri-state area) I get the impression that information is often hard to find and hard to understand. This could of course be caused by cultural or lingual differences since I'm neither American nor a native English speaker.
The emergency room is the last place you’d go for a simple test. The only reason you should go to the emergency for a test is if it’s heart related or you think you may die (an emergency.)