I am looking into buying a pre-certified Lexus 2007 RX400h SUV with about 29k miles. I know the battery warranty is far from being expired, but would still like to know how much a replacement battery would cost. On the internet, I'm only find costs of about $3k, but that was in 2008. It's now 2010 and wondering if the cost has gone down. Any info is appreciated. Thanks.