1. Where would the WEBOOST controller be installed inside the coach

Normally I've seen this mounted in one of the front compartments above the windshield.

2. The stairwell cover stopped working. I finally found the fuses in the compartment under the drivers seat. I removed the fuse and put it back in. Now works like a champ. Is that normal?

No, the normal issue with steps is lubrication on the hinge points, or the small magnetic switch on the screen.

3. My Right turn signal doesn't flash. The signal stays lit on the dash then eventually it goes off. 

Sound like a light bulb?

That does sound like a bulb out, or the flasher. It is normal for the flashers to not work if there is a dead bulb.