I called the support line with some interesting information. Hope someone can offer advice.

My thoughts:
I needed this kit for a tractor that I use time-to-time so I don't want to leave any equipment in the cab where someone else could take it. Also not able to mount an antenna outside. Then I wanted to be able to use it at home as well. So I thought I could buy the following:
- Buy the Onyx Home Kit so I can use it at home or outside
- Get a cigarette power adapter for the tractor

I was told this wouldn't work by Sirius Support:
- docking stations can't be switched with a different power adapter (i.e. going from a typical power plug to cig lighter). So I need to buy both the home and car kit.
- home kit antenna will not work for reception in a car so I also need the home and car kit. (though I can't mount the antenna outside and need it inside)
- home kit will not work on a dash since it has to be strapped down. (to me I don't see why you need the receiver strapped down as she's maybe just reading what she's been trained to say)

Any advice?