The 12v direct plug-in he by far the easiest way to go, and if you are getting a new machine, tell you provider that you need that ability. All of the Respirontics units are, but some providers will not provide that brand. There is nothing that prevents you from shopping providers. I did find that the new Dreamstation does require a new 12v adapter cord, as the plug is not the same as previous models. And it will probably be cheaper to get a cord on the internet than from the Durable Equipment provider. They charge about double, and insurance does not cover it.