Hopefully this will help. I haven't been to the dealer yet to order, but this was a reply from a man that works at another gm dealership. I was in the same situation.
"Below I included a copy of your Outlooks build sheet with all RPO option. If you notice, you do have AP8 which most, if not all of the 09's have. You also have TB4. This is a manual lift gate option. Unfortunately, there is no 2way remote starter for your specific vehicle build because it does not already have AP3......but.......you can however have your Dealer install part number 17801236 that will upgrade your Outlook to a factory style AP3 remote starter. I included a copy of the starters below. Now from my experience, I will be blunt....the 2way remote on my Acadia is a piece of crap. Our Acadia has every factory option available and to be honest, the original starter that it had was no worse than the one I installed. The range increased by maybe 10 feet and the battery in the transmitter is always going dead. It does have some cool little features but it's not worth the trouble or the money. The transmitter is also HUGE. Looks kinda silly really. Go see your Dealer with your VIN number and ask them how much to install the basic remote starter. "
"By pressing a button on the key fob, the remote start system starts your parked vehicle. Great for pre-warming or pre-cooling your vehicle. Seamlessly integrated with your vehicle's anti-theft and remote keyless entry systems.With Manual Lift Gate, For Use on Vehicles with Extended Range Remote Lock Control (AP8), Includes 2 Fobs" 17801236