Key & fob replacement for 02 Sebring lxi coupe ?
 

Bought this car a few weeks ago for daughter to use/backup and it only came with one key. Owner said that's all they were given when they bought it for their son a few years ago. Went to have spare keys and fob made today, and twice, the keys wouldn't work. Lock guy said it must be because my key is so old. Also was told that this model did not come with a fob , therefore, can't get a keyless entry made. So, I still just have the one key. I've been searching for info, but I've found very little relating to my coupe, everything I find is for the 2 door convertible. Anybody know where and how I can get keys and whether the remite fob thing is true ? Any help is appreciated !!

The dealer would have the correct keys for the car, but they will cost a little more.
The locksmith has no idea what he is doing.

One thing that you can do in case the key is locked in the vehicle is get a key made that does not have the programmable component in it. A plain basic key that will not start the car, but it will open the doors.
That would allow her to open the door to get the real key when it has been left in the vehicle and would be easy to store in a wallet or purse.

Be aware that the coupe is a totally different car from the sedan/convertible. Coupes were built by Mitsubishi, sedans and convertibles were built by Chrysler. They have almost no parts in common. I don't know whether the keys/fobs would be different or not. It's unlikely that the dealer will be of much help, given the age of the vehicle. After 10 years, dealers lose interest. You might find some information on Mitsu forums.