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I have a 2000 Malibu and 2003 Honda CRV, both with keyless entries.  A couple of weeks ago we had a break-in while on vacation and they took the keys to both of these vehicles (but left them in the garage).  I've been looking to replace the transmitters, but was appalled to find out they were around $150 each to get new ones programmed.  

On ebay they have several for sale for both of them and claim they are easy to program yourself.  I'm skeptical of getting something for $10, that normally costs 15x that much, so I am wondering if anyone has an experience with this.  CAN I do it myself, or is this something I just need to suck up and have done at the dealership?