In other vehicles I have gotten homelink garage door openers for about $2 (US funds- CHEAP!). They are easliy found in the sun visors of Dodge/Chrysler cars. I tear apart the visor, and mount the unit anywhere I want. The plus is that these are hard wired to the donor car and are set up to run 12v already so the install is a snap. They are much cheaper at the salvage yard than a garage door remote is at the home store. This link is just for picture reference to what I use- it is not me selling this unit.
https://i.ebayimg.com/images/g/u1MAA...Gif/s-l500.jpg