I am locked out of the garage without a remote opener. There are no windows and no doors to get in. What are some ways to open the garage door without breaking down the door?
Typically, garage openers have a release pull that hangs down from the track. When closed, this release will be close enough to the door to get if you drill a 5/8 inch hole about a foot under the where the opener attaches to the door. Fish for the line with a wire coat hanger and then pull to release. It will take a couple of tries but you should be able to do it.
Once open, go to your hardware store and get a garage door quick release lock and install it into the hole you just drilled. In the future if you have a power outage or a failed garage door opener you will be able to get back in.
All you need do is borrow (since you can't get inside to access your own supply of tools) a regular, flathead screwdriver. Place the blade of the screwdriver against the keyhole of the garage lock, just like you are attempting to unlock it with a regular key. Then, bash the back of the screwdriver, driving it into the lock. This will be sufficient enough to jar the lock open, without damaging the lock. You may need to use a hammer to hit the handle of the screwdriver.