Making a car difficult to steal

How about keyless start but need to have a key fob in the car to start the car with the push button. That is what is utilized in my moms 2011 Highlander and is great don't even have to have the key out of your pocket

I'd love to find something like that, but so far I'm pretty much coming up blank for some kind of retrofit. That's why I'm here asking if anyone know of such a thing.