I hate having a garage door opener clipped to my visor and my 2014 M235i didn't come with homelink buttons.
Here is my solution for those who might be interested. Purchase a momentary spst switch and install it somewhere in your car. A momentary switch is like a horn button. The circuit is closed only while the button is pushed just like your garage door opener. Solder into your garage door opener with a length of wire and you have a seamless install that is oem quality. I installed mine on the drivers door in the panel that houses my window and mirror switches. There is plenty of room to store your opener underneath the panel where it is out of sight. I wrapped my opener in a small piece of carpet pad so I wouldn't have any rattles. I started drilling from the back side of the panel with an 1/8" drill bit right into a sleeve with a hole in it so I would have my button perfectly centered in the panel. You can see another just like it right next to the hole I drilled. Use increasing size drill bits until you get to the diameter of the shaft of your switch. Mine is 1/2" but it will vary depending on the switch you buy. I used a dremel to shave away the four "fins" on the back side of the panel to make a space for the lock nut on the back side of the switch. Do this before you drill so your bit won't bounce around while drilling. Here are a few pics of the install. There is one thing I am going to change however. The switch I picked up at Radio Shack is gloss black and I have another on order that is matte black to match the panel where it is mounted. Pretty nice mod for an investment of under $5 for a switch and much cheaper than the homelink option probably.
