I lost my key for my 2003 Lexus. Its the key with a remote. Where can i go to get a new key and how much will it cost me.

 

please tell me you have another one Key with a remote

the key with remote on it is called the master key
only a master key can program a new key to the car they all have a immobilizer chip inside that disarm the car security system
if not your option is a locksmith or dealer
there is DIY video on YouTube that require you to have a Techstream VDIM Mini VCI OBD2 Data Cable and software but it say you need to buy a token from some European website that seems too shady for me
I also have a 03 GS 300 just had a master key cut but the have running into remote program issue that I am trying to figure out
anyway, the lock smith charged me 250 out the door, hope this help

 

The dealership has a program that will do it for free you just pay for the keys they will provide you the ECU and labor free

do a search, good luck