I agree with the others - starter motors don't fail like they used to, especially not on a 5 year old car. That's the trade-off you make though when you 'send it to the dealer', if paying the $600 bill is worth the convenience to you, then it doesn't matter what the real cause is...you pay the money, you get your car back working.
I went out earlier and took the Escalade, just because I haven't driven it in awhile....No blower motor up front. Rear HVAC works fine, but the front blower doesn't come on regardless of setting. I recall taking the blower motor out (an easy 10 minute job) a few years ago to clear some debris from it, so maybe the motor has finally given out, or the resistor (which is actually more of an electronic control module in this case) is bad. Too cold and windy to investigate now so I'll check it out tomorrow. Luckily, both components are easy access under the passenger dash.