Newbie question about quick overnights

Most rest stops I've seen don't allow overnight parking but some states do. If it's allowed I would use it. Truck stops can be hit or miss. They are usually loud and if they are small the truckers don't like us taking a spot they feel should be theirs. Wal-Mart is usually easy with several websites and apps that help find those that do or don't allow it and they are used to us when other businesses sometimes aren't sure what's allowed or if they would have insurance/liability issues. Churches have been good if I was visiting a member who would vouch for me, but I guess I was reluctant to ask if I didn't already know.
I usually Wal-Mart it if it's just a stop over.