I installed a keypad for my garage with two codes - one for the garage door and one for the golf cart door. Originally I got a 'universal' keypad from Home Depot, but it didn't fit. I had to get it on-line and I installed it myself, but I'm sure you can get someone to come out and install it for you.
I also installed a keypad on my front door deadbolt. I got it at Home Depot and it matches the finish on the door handle. The hardest part about that was removing the old deadbolt - the directions were terrible
but I finally found a video that showed me how and I was good to go.
So now, since my car is keyless, I don't need keys for anything (except my mailbox - hmm.. got to work on that). My purse is so much lighter!
Just make sure you use a code you will remember - like the last four digits of your SS number. When I add a temp number I use the last four digits of the person's phone number. That way if I need to delete it it is easy to remember. I like the idea of an emergency number.