I don't know if it's a gray area, since your system is essentially empty, because it's really not "empty" just because there is no pressure. You're supposed to pull a vacuum during extraction. Not a complete vacuum like you need to do for evacuation, but a pretty good vacuum at 10 or 20" (depending on the licensing need of the technician doing the job). Even an "empty" system will have refrigerant in it, just not under pressure. But I'm sure that people take things apart all the time when they have leaked out, without sucking them down with the extractor.

Yes, you can do it yourself, but you'll need some tools. As Larry said, it is important to keep the plugs in the dryer until the last minute, when you're ready to put it in and immediately evacuate the system. And don't hold it under vacuum for a period of time to test the system for leaks or for any other reason. A vacuum means that air can be drawn in, with its moisture. After achieving the desired vacuum level (or waiting an appropriate time if you lack a micron gauge), immediately let the refrigerant in to break the vacuum.