I usually listen to that little voice that says turn around and get outta there after...
1. The person moping the floor turns out to be the waiter.
2.The waiter/janitor leaves the mop bucket and without introduction asks what do you want?
3. The table utensils need a good wipe down before use.
4. The fajitas have a grey color and no sizzle.
Listen to that little voice.