Deaar Trudy,
I volunteer as a mechanic at our church where cars are donated, fixed up, and given to people in need, mostly single mothers who lost their transportation due to excessive hardships. I share this because I get into many donated vehicles with keys locked inside. Most vehicles are opened with a very thin metal stock, about 1/2" wide and 2 feet long with a notch cut into one side. You slip it between the door window and the rubber strip on it's bottom. You fish around by the door lock lever, key area, or door latch, hook it on something, either push down, push sideways, or pull up using the notch to hook it on something. With patience and a little bending of the metal, you should be able to unlock one van door. That piece of metal I describe can be purchased at most auto parts stores for around one dollar. It has so many different names, a "correction, SLIM JIM" being one. Here is what a nice one looks like with multiple notches. I have one at home that I made myself out of scrap tin. If you make one, just be sure there are no sharp edges to scratch or cut anything.
It is so easy to break into a vehicle without damage to it.
The only thing you could do to make it harder for a thief is to chain or cable the two van doors together on the inside, assuming the door handles are hollowed to allow a cable to be get strung through them. That way thieves would have to break glass and crawl through the broken window.
Then there is consideration to the RV entry door. It too needs to be secured with an extra latch close to the floor that they could not reach through a broken entry door window.
