Adding a second a/c

[Muscrat]

Thanks for the help on the other post I made. Thanks everyone.
Here another question.
I'm looking to add a second a/c in the front skylight hole. Which brand unit to go with. New or used?
The factory one works fine but runs all day. I'd like a second unit to run during the day and use factory unit at night so it's quiet. It's a 30 amp service so I know I will have to have an external plug for it.
Any advise would be appreciated.
Thanks in advance.

[Festus2]

I would stick with either a new Dometic or Coleman. Parts and service for both of these units are readily available should they need repair or servicing.

[michol02]

I installed a second AC (15K btu)a while back. I used a 50 ft 10 gauge extension cord(cut end and hard wired it to the AC), snaked it through the ceiling, down the back of the frig., and into a cubby hole behind the outside shower fixture. The plug end sticks out of a hole in the fixture box. I just pull out as much as I need and plug it into the 20 amp park power. I cut the lip off of the roof vent so the AC gasket would fit. I had a smaller unit(7500btu) there previously, but left the vent lip and used 2 AC gaskets. It worked, but looked funny sitting up higher than the other AC.