Growing up in the Boston area I called that four-wheeled thing you push around at the grocery store a carriage. Now it's a cart. Same for those two-wheeled things that people who walk to the store carry their groceries home in. Formerly "two-wheeled carriage," now cart. A friend calls them "blue-haired lady carts," because she associates them with older women.
To me "out of pocket" refers to money. As in, stuff you pay for out of whatever money (cash or plastic) you're carrying as opposed to what is already covered (e.g., for a vacation you pay in advance for your hotel and rental car, but you still have to pay out of pocket for meals, souvenirs, park admissions, etc.). I've never heard it used to mean out of the area or not reachable.
My mom says "mind your own beeswax" as a slangy alternative to "mind your own business." She's Boston-born and raised.