I need a new FOB. I tried a couple on eBay but they didn't work. So what is the best way to replace the key and the FOB? One was an after market and it would close right when assembling the other was an original key but when I tried to swap my key and buttons wouldn't work because it was totally opposite of my FOB

 

If you are wanting to replace the key and fob, you need to get the new key cut, then program the key.

The Autel AP200 is a relatively affordable programmer.

 

The electronics in the key fob are where the immobilizer transponder is. That can be transferred to a new cut key and fob shell without programming, if it currently starts the car.