Post #3 is right on. As long as the locks are Kwikset, which they probably are.
You'll likely only have three locks total. Two at front door and one at garage entry door.
You can get a Kwikset re-key kit from Amazon, Home Depot, Lowes, & hardware stores.
I'm not sure how necessary it is to change, but for peace of mind maybe.
Here's a link to the kit at Amazon. $9.47
Be sure to watch the 15 second video at that link.
Robot Check
(the link says "Robot Check" but it does work)