Mobile homes have an inherent water intrusion issue around windows and doors. This is mostly because of the condition at the eaves. Due to a lack of eave over-hang the rain water from the roof simply runs down the walls and seeping into the living-space.  Over a period of time this can cause major damage to floor and walls.

A metal roof can resolve these issues

A custom gutter over the entrance is a good addition.

To reduce probability of water intrusion, the roof panels should extend 6" to 12" beyond eaves

With the custom gutter, one can unlock the door without getting drenched.

Roof was damaged and interior damage had almost begun.   Purlins (often miscalled "furring strips") were applied over existing shingles followed by 1/4" fan-fold insulation. The eave trim, panels, rake (gable) trim and vented ridge-caps were then installed. If images do not show, copy and paste this url into your browser : http://handymanedwardnc.weebly.com/roof-sept-2013.html Rather than using standard residential rake trim, residential corner trim was installed. I think the corner makes a better looking gable.