Is there a way to get new locks (4) that use the SAME key?

Yes you can get locks the use the same key. Been a while, but it was done at a big box store, there is a code of sorts on the packaging. The store locksmith re keyed them.

Yes, just match the # on the lock. Ask the person in the dept that deals with locks at Lowes or any type store like that. You can also get extra keys made.

We had this done at Lowe's when we bought new locks for our home.....and any specialty key/lock shop can do it too

Most large home improvement stores like Home Depot and Lowe's carry multi packs of door locks.... ask one of the sales people there for help finding multiple locks with the same "code" number.... you can normally find at least 2 with the same "key" number or code..... many offer a key matching service... where they alter all the locks to use the same key.... but they may not be able to do it while you wait.

if you are talking padlocks... most home improvement stores sell them in multi packs... if you are talking door locks.... Home Depot and Lowe's both offer a service to alter multiple locks to accept the same key.... but they may not be able to do it right away or while you wait.

They can key all the locks to one key where you buy the locks. There are kits to rekey locks but it does take a little knowledge and skill. I was rekeying office locks on a regular basis at the nursing home I worked at rather than replacing locks. Commercial locks were around $109 while a rekey kit was about $20. Always had a supply of pins and springs so most of the time didn't cost anything.

Most hardware stores can key the locks to the same key right in store.

Check your local big box home improvement stores to see how many you can get with the same key, they should come in the same package. If not enough, a locksmith should be able to rekey what you need.

Any key store can do this. It's especially practiced if you go to the same store where the first key was bought. I know a licensed locksmith service for homeowners and businesses that will help in this case. When my grandmother was building two houses opposite each other, she installed locks everywhere she could open with this key. She hid this key in a hidden place, which only relatives knew about. That way, we could always go into any of her houses when we came. I think it's a little dangerous. It is better to carry this single key with you.

Of course, it's a piece of cake. There is nothing complicated here, as long as the locks have the same core

Of course, it's a piece of cake. There is nothing complicated here, as long as the locks have the same core. Much scarier when your key is stuck in the door, and you can not open the door. In that case, try to remove the key by rocking it from side to side while pulling it toward you. If you can't get the stuck key out, you should repeat the whole operation. You can use the pliers, but in this case, you should be extremely careful not to break the key. I even had a broken key, and part of it stayed in the lock, and I couldn't get it out. Then a locksmith came to my rescue https://mylocallocksmithtx.com/grand-prairie/.

We did this a few years back when we changed the locks on the doors to the porch (opposite ends)it did take some skill for the homeowner to do , but not impossible.