I also have one of the GP logistics one (links below) as well as a telescopic one. I like them for different reasons, the step ladder is better for putting up a tarp if expecting rain/snow but the telescopic is good for getting on the roof to clean the solar panels, check the roof etc.
I have a built in ladder on the back of the camper but it doesn't have any handholds on the top so I really have no idea how it is supposed to be used safely.
https://www.amazon.com/GP-Logistics-SLDD7-Compact-Folding/dp/B009IJUL4O/ref=sr_1_1?ie=UTF8&qid=1506912785&sr=8-1&keywords=gp+logistics+ladderhttps://www.youtube.com/watch?v=EmsOd7atirI