If your car has homelink (built in garage door opener) you might want to check out using an X10 transceiver as a way to control your home automation from your car (within distance, driveway)
Common misconception, your home automation gear doesn’t have to be X10 to take advantage of this. You just leverage X10 as a bridge/transport between your car’s transmitter and your home automation server.
Simply buy a cheap X10 transceiver and USB interface (check ebay, kijiji, craigslist). You can use this to receive signals from cars with a “homelink” universal unit. Typically meant for garage door openers.
I currently have my homelink unit in my car configured to 1) open/close my garage, 2) Welcome Home Mode: Turn off house alarm, turn on exterior lights, turn on main level house lights. 3) Away Mode: Turn on house alarm, turn off all house lights, turn off exterior lights, indicate to devices like thermostat.
I use an inexpensive X10 transceiver module and an X10 USB dongle. I connect this to my Linux server (or use a raspberry pi), have a script intercept it, and perform actions like controlling my lights, security system, even thermostat.
For me this is great. I have a driveway that goes to the back yard of my house and to a detached garage. It’s really cool being able to come home and with one button press, I can light up my entire path back to my house’s side entrance. Or being able to pull away and turn off any lights I forgot about, without having to dig for my phone to do so.
Range is limited in my experience. 30 feet perhaps more. Depending on your layout you might want to set up a couple transceivers. In my case, I have one transceiver in my garage and one at the front corner of my house. I have a L shaped driveway that wraps around my house and this seems to cover it.
X10 Transceivers like this, http://www.x10.com/tm751.html are really inexpensive if found from the right source. I paid pennies on the dollar for boxes full of X10 stuff on ebay and kijiji. You’ll also need a cm19a or cm15a interface. Do your homework before deciding which and buying.