I’m in the process of renovating a large rental house. The house is already covered with Zigbee and Z-wave. And there is a central SmartThings Hub. It also has an old electric driveway gate. The gate is within range of the of Zigbee and Z-wave. I would love to have a way to automate opening and closing the gate. And since it’s a rental, I would like to have a keypad control on the gate or on the attached wall. I thought of just using a Schlage Electronic lock (I know it’s not weatherproof). And placing a plastic cover on both sides:
And with that lock, I could just program a simple IF the lock is unlocked/Then send a open signal to gate motor relay. But then I kind of get lost in how to make sure the gate is closed after cars or visitors pass thru. I’m trying to use something more off the shelf. Instead, of engineering something from scratch. I also want it to integrate with my current Home Automation system. Any ideas?
You can see what other people have done for gate control by going to the quick browse lists in the community-created wiki, looking down towards the bottom of the page for the project reports section, and then choosing the list for “gates”. 
As far as the keypad, see the following FAQ:
gate control - just need to change icon
then just use smartligting app (for example) to turn on/open gate