Thanks for the questions,
I just use a standard industrial gun. They cost around $1500-$2500 for a semi decent one, dont buy a cheapie off ebay they explode.
In these cirmstances for a quick job I use 1 colour, i am using whisper white at present. However I generally spray roof white with a slight tint, and the walls whisper white, then cut in about 6 inches up top.
You masking tape everything up. Windows, rooms, lights, fixtures and fittings(yes even the kitchen appliances).
I might take a video of the airless if i head out there on the weekend.
Anyone can spray with airless.