My experience is at NJA. In addition to what the other guys have said, you'll also have to pull all the liquids off the airplane when parking it outside a heated hangar in cold weather. 30+ cans of soda, several bottles of wine, water, sparkling water, juices, all of it. You'll put it all into soft coolers or plastic tubs and have the FBO store it for you indoors. You'll also need to dump the water supply for the lavatory sink and (if applicable) the coffee maker, and the get the blue juice dumped. Then you can finally go to your hotel.

When you get back to the plane, you'll have to reverse the process and put it all back where it belongs. It's a tedious pain in the neck, so a heated hangar is always a good thing if you're lucky enough to find space in one when you get there.

Another of your major duties is keeping the plane stocked with the aforementioned liquids, along with snacks, napkins, stir sticks, sugars, creamers, plates, plasticware, cups, and so on. Supplies are kept at many locations around the country, and you'll normally replenish when you pass through those cities. Checking expiration dates on every soda can, tossing expired/broken stock, updating magazines, charging onboard iPads, and more, are all part of the duties.