How "SW"?  Try the "RV Parky" app.   Put your city and it will give camping spots around it, along with reviews.  It will show parking lots that allow camping as well.

There were a bunch of deregulated camping spots available out west but I don't notice much at all around here.  Maybe some of the dedicated park and rides near the freeways.  

If they're staying for a few weeks I'd look at a month long rental spot at a campground.   Then at least they would have somewhere to dump tanks or refill water (or maybe full hookup).