So I went with the mid-range option above (using the Microbot Push/Prota) and having pretty decent success. I built a cradle for it out of a small piece of wood and a decora light switch cover. (one of the screwless kinds for a cleaner look) I put a little rubber bumper on the key fob to make it easier for the Push to do it’s job.
I went with a Raspberry Pi 3 as the hub for the Push and installed the free ProtaPi OS. ProtaPi seems to run very sluggishly. Set up is not trivial either. You don’t need to know how to code, but using the mobile app to configure the hub is a major PITA. I have to assume buying the ProtaS is at least easier on the setup side. Still, the cost is hard to beat and Naran has confirmed they’re working on a version of ProtaPi to support the RPi Zero W. So it would be even cheaper.
I wanted to integrate this into ST, because I wanted to literally say the words, “Alexa, turn on the car.” I created a virtual switch in SmartThings called “Car.” SmartThings is not needed to make this work however.
So here’s how everything talks to each other.
"Alexa, turn on the car, please."
Alexa - SmartThings - IFTTT - ProtaPi - Microbot - Key fob - Car
It seems like a lot of steps, but there is acceptable latency. Consistently getting about as much as the video above shows. I just tuck the pi and the cradle away out of sight.
Note: You do not need Smartthings for this. You can simply use IFTTT directly since there is a native Alexa channel. I imagine it probably shaves some time off of the response as well.
"Alexa, trigger the car, please."
Alexa - IFTTT - ProtaPi - Microbot - Key fob - Car
Would love to hear your thoughts!
And here are links to buy the stuff used in this project:
Microbot Push: http://amzn.to/2rRxAMo - $50
Prota S Hub: http://amzn.to/2s1ReHD - $90
Raspberry Pi 3: http://amzn.to/2sJ1ylI - $35 - with Prota Pi OS: https://prota.info/prota/pi/
Decora light Switch cover: http://amzn.to/2skkvxK - $5