Can it be used for rustoleum paint, am going to spray outside of mobile home.

That would depend on whether it was an oil based or latex based paint. Oil based could be thinned appropriately for use in this sprayer. If it is latex based paint, the Control Spray Double Duty is not intended to spray latex paint. It is too thick. For this application with either oil based or latex based paint I would recommend another sprayer that Lowes carries: The Wagner Flexio 570. It has a more powerful turbine capable of sprayer either either latex or oil based paint without thinning.