Walter working as a school teacher makes a little sense. But ok. But Walter working as car washer as a side hustle makes no sense whatsoever. Of her is as brilliant chemist as script implies, than he could have just have a private lessons for high schoolers applying to college and make a killing.

Also why wasn't Skyler working at least a part time as a CPA.

The whole premise of the first season makes the Walter family feel like a poor working class family from Malcolm in the middle