I'm looking to buy keyless entry transmiters (because now i have only the key....), but i see that some of the options have one extra button (remote start). How can i know if my car has the posibility to use the remote start?

I can't find the amplifier in my Malibu 2010 LT. I searched on internet and i found out that it has to be under the passenger's seat - nothing there. After more searching someone said it can be under passenger's rear seat - nothing there, again. In some page i read that there can be no factory...