Woman here needing info about buying device that starts car & heats for winter?

I don't know anything about them and I live in "snow country" NYState. I'd like to have one installed in my son-in-law's new car as he takes my infant granddaughter to daycare daily. What do I need to know about these devices? Who installs them and approximately what should I expect to pay? It'd be nice to have the car warmed up and partially defrosted before putting the baby in the car....and it'll be an early Christmas gift :D. Thanks for any info!