Ok...Prime just the side that will be visible. Also do the ends and any joints. You don't have to do the backside unless it's going outside. If you are planning on doing this pre-installation, only do the first coat of paint. Save the second for after install, that way you can cover up nail holes and make it look really nice. If it's going to be a day or two for install, clean out your paint tray. Wrap your brush in plastic wrap or a plastic bag. (Shopping sacks work well.) Do the same with your roller, handle and all. Then put both in a garbage bag and wrap it up tight. They'll stay wet and usable at least a week. You can also put them in the fridge, but I never have room, so I don't. The Bin dries super fast. (I really love that!) I would bet by the time you get done priming, you can turn around and start your first coat of paint! You can do it in the garage, just make sure it's at least 52 degrees F. Anything less than that compromises dry time and adhesion. You can do your first coat of paint in the garage too, as long as it's warm enough. You're very welcome. :)

what coating does the ceiling have...sealer/stain/topcoat....a combination? I've used deglosser to older surfaces w sheen...then painted without an additional primer step. It worked well...getting newer paint that has priming/painting in one step may be your key to this. But you have to assess what is the top coat on that ceiling surface that you are trying to get the paint to adhere to. What is the age of it? You might be well served by hiring someone. Ceiling surfaces are so much more easily dealt with by those who do them regularly....not that you can't...but use your valuable time elsewhere is my best advice.

Start by providing photos. No one can really give good suggestions without seeing the space you're dealing with. Take pictures of rooms you're asking about from all four walls so we can see doorways, windows, adjacent spaces. What furniture do you plan to bring? Start an Ideabook on Houzz called "knotty pine" and save those that appeal to you. Is this a vacation home or main home?

I generally would favor painting the ceiling and leaving the walls, but since you want to showcase your antique furniture (assuming you have other pieces besides the sideboard shown here), then lighter (or at least non-wood) walls would be the way to go. If you don't want to commit to paint, since that will be fairly permanent, you can also think about using thin wallboard over the pine and painting that the color you want. I might want the wall behind the sideboard painted and if you are open to painting the brick, then paint that, too, although you're going to have to love how your woodstove stands out against painted brick.