I'm in an RV van, not stealth at all, but when traveling through cities I wanted to visit, I had a list of things to research:
City Park, Walmart, Lowes, Cabellas (some offer free water and some have dump stations), Casinos, Planet Fitness (since I have a membership; go in, use treadmill, take glorious spa like shower, ask about parking overnight), Cracker Barrell, Rest Area if it's a really nice one. If those did not work I might consider hospital parking lot (less risky) or in some cases a hotel parking lot but that to me is very risky. If there was nothing on freecampsites.net in the city, I could also check boondockerswelcome. It's $5 or so to driveway surf that way but it is also Welcomed, which is awesome. Also, I found there was an attitude in some paid RV parks, and that surprised me. My van is a 2004 so sometimes I'd get comments like "oh the old van conversion huh?" and I'd say, "well, it's factory made" and they'd settle down a bit, but I did find them not friendly to stealth vehicles at all and I thought that was sad. It's a lot to hunt down a great city spot. Need to learn more about it myself. Thanks for the thread.