Constant powered.

 

As long as you use enough fuel stabilizer, the amount in the tank shouldn't matter all that much. If you use a smart trickle charger, no worries there either. A battery tender will keep it viable for the winter. As for other stuff: make sure you've got the right coolant mix for the temperatures you will see, change the oil just before you store, wipe down the leather with some leather conditioner, put a good coat of wax on, and don't worry. Are you able to jack it up so the tires don't flat spot?

I do all of this with the exception of jacking it up. I heard that the Cayenne suspension doesn't like the wheels to hang as it will sit funny in the spring when you lower it again. I've also read that modern tires aren't prone to flat spotting. I've had no issues and it sits six months per year.

I drive it up on 4 - 1' square 1/2" thick pieces of plywood as this is supposed to prevent damage from alkaline seepage from concrete into your tires. I'm not sure if this last one is necessary or not, but for the cost, who cares.

You will definitely need the battery tender.

 

My car is a weekend warrior, but I keep it hooked up to the tender during the week. Using it this way is recommended because it keeps the battery at optimal level and is good for the battery. In the winter, when the car gets no use, the battery tender is used to avoid draining the battery completely.