I hope you check the batteries often of your keyless entry lock. One weekend a few years ago I was taking care of a friends 2 kids and her then boyfriends 2 kids (who is now her husband) while they went for a work conference / weekend getaway. I picked the older two up from school and then the grandmother dropped off the younger two. They had a keyless entry lock and no one had keys. My luck had it that that was the weekend that they batteries died in the keyless entry. I had to call a locksmith. I couldn't go anywhere because the car seats for the younger two were inside. I had to call and have pizza delievered and we ate outside while the locksmith got us in. Four hours, $200, and a full blown headache later we were finally inside. To make matter worse this was the first time I had met the two younger kids (her now-husbands children).
The point of my story is please make sure you check the batteries - or have a key as backup.
To the OP - if the existing locks are older I would suggest just replacing them with a set. Our garage door, french doors, and front door all use the same key.