I was just waiting to pickup my online order at Sears store, found a Key Duplication Kiosk there, a guy is duplicating his key, I have asked how much does it cost, he has replied, standard is $3 but if you stick your original key in and then cancel the transaction, they will pop up a 50% off code which you can apply right there. Effectively I got a brass key for $1.5. I guess its a good idea to make a duplicate key(home/car etc) and keep it with your friend's home near, so that it could be handy at times.
Update: Its not a must to look for Sears. There are many places where you can find these kiosks . You can search their site with your zip code here: [key.me]https://www.key.me/kiosk