I've noticed that most cars have a heater that takes a few minutes to start after the car has been started, presumably because it derives its heat from the engine which hasn't heater up yet.
Are there heaters which don't use engine heat and thus start up at once? What are they called? Can you add it to an existing car or does it have to come with the car? I really would like to get in to a car that blows hot air at me right away.
The cheapest way to do so, would be to add something like this aftermarket accessory. Looking for any in-dash options would likely be more expensive.
Another option that you could look into is getting an engine block heater fitted. Essentially, you plug those into a wall outlet and they warm up the coolant which both helps with cold starts if you're in a cold climate, and you should get warm air out of the heater fairly quickly compared to a car without a block heater.
VW beetle and other old air-cooled volkswagens (bus, karmann ghia, 181/thing) burn gasoline to directly generate heat, and then they blow hot air into your cabin. They can work even when the engine is off, but they will run out the battery.
This video shows one in operation.
In my experience, they put out so much heat that it makes your legs feel like they are burning. It was easier not to use it; but then again I lived in Phoenix.
