There is no safe storage area on the roof of a CA motorhome (assuming the roof construction hasn't changed since my 2005 unit was built). The roof is mostly made up of high density styrofoam between 2 pieces of luann. There is a CruiseAmerica youtube video from about 2007 that shows an optional ladder and roof cargo rack. CA no longer offers it. Most RV shops that I know of do not recommend them. The mounting points get stressed from the cargo that is strapped to them and become a source of water penetration.
A CA motorhome has no jacks, no slides, no awning, no ladder, no outside steps, and no over-the air TV aerial. They might drive off with the stairs extended or the batwing raised. These are the things that renters break. CA does not renters up on the roof, so there is no ladder.
A ladder can only be added if the coach was built with the structure in the back wall to support a ladder. If an RV does not come from the factory with a ladder installed then it is very likely that the factory did not include the structural reinforcement in the wall for a ladder. The reinforcement is not for the ladder as much as it is for the weight being loaded on the ladder - bicycles, chairs, 1 (or 2 people) climbing the ladder. Without a reinforced rear wall, the ladder's mounting bolts would start to tear away from the wall from the vertical load placed upon the ladder.
2005 Cruise America 28R (Four Winds 28R) on a 2004 Ford E450 SD 6.8L V10 4R100
2009 smart fortwo Passion with Roadmaster "Falcon 2" towbar & tail light kit -
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