BFL13 wrote:
It could be just the same as any car, nothing to do with being an RV with inverter, etc. A "dead battery" that won't crank at all (might get a click) is often a bad connection at a battery post. Clean that up and tighten and starts right up. Not saying that is for sure what this is, but could be.
My feeling also. Take a look at the age of the battery, you just might be due for another one. Other simple thing is a radio was left on or some dome light. Assume you have a van and not an RV at this point.