This is 100% wrong. ALWAYS apply ceramic coating AFTER any PPF or wrap.
Exactly. The PPF will not adhere properly to ceramic coated paint. You will also need to strip off any waxes used as well.
This is correct. It helps my car is white, but it will stay clean for seemingly forever. A quick rinse and it looks almost perfect. Depending on the coating used and the layers used, warranty varies. See below for examples:
https://www.wildwrapz.com/detailing (scroll to the bottom)
while i don't recommend this AT ALL, PPF and Ceramic helps dramatically with reducing/preventing swirls/scratches. if you are short on time, and can't wash it at your residence, there are tons of "drive thru" washes that have bays where you can jump out real quick and spray off your car with pressurized water/soap. even though the water at these places is still recycled, its better than "no touch" drive throughs, which are better than anything with brushes that touch your vehicle.