Adding a fan to a preexisting roof ven

My old jayco had power at the bedroom vent because the ceiling light was near the vent opening. So that line was hot all the time and you turn the light on with a switch thats on the light. They put the fan in the bath because of odors obviously but it also keeps the noise away from the sleeping area. This wasn't cheap but I installed a fantastic vent remote control thenty five zillion speed or whatever vent in the bathroom and have the remote control by the bed. If you are set on putting a vent fan near the bed I would seriously consider one that is variable speed and quiet. It was one of my most painful up grades but well worth it. I run the bath fan and open a window near the bed. Its also VERY easy on the battery