We have the full Sirius XM setup; portable speaker system, home system, auto system. In the motorhome, I placed the antenna 'puck' in the motorhome's center ceiling vent. This way, I'm never in a location where I can't receive the signal (unless I'm going through a tunnel, or parked along a tall building!).
I cranked the vent open, went atop the roof, and fed the antenna's connection end in and through the small hole the crank is centered in. The antenna is magnetic, and I simply attached it to the steel support brace that runs down the middle of the vent. I fed the wire across the ceiling, and using Command Strip products, routed the wire over to the cabinet wall and down to the Sirius receiver.
We have one receiver, and simply take it with us, along with the remote, between house and motorhome. The Aux cable is routed in a similar manner, and is out of sight except where it feeds into the aux port -- about 6" of cable shows, so no big deal.
In over 7,500 miles of mixed roads, the magnetic puck end has never moved, and we never have to worry about reception. We have Fantastic fans on each end of the motorhome, and never use the center vent, so for us it's a perfect location.
2016 Coachman Leprechaun, 319DS, Motorhome, Dodge Durango Toad