is that a waste oil heater ? if so how well does it work and what's the consumption rate?
Also not to be a smart a-- but the ceilings are pretty high and obviously that's were the heat is going to go. I dropped the ceiling's in non critical areas, insulated the ----- out of them and it made a huge difference in heating and cooling costs. but maybe you need the height

Satin white is fine if you spend some money and buy sherwin williams superpaint or better, and use their primer not cheap stuff. The frp panels are fantastic, you do not want smooth it looks like [censored], the plastic trim for frp will discolor/yellow after a while and need sanded and painted. Sequentia frp is way better than the other brands. Frp cleans fast with 409 a brush and a hose.

Going to disagree that satin anything is a good choice in the shop.

Paint will actually be Sherwin Williams we use it on everything. Staying away from anything textured already made that mistake in the garage. The paneling looks like a good idea but with some curtains on my prep station I think most will be contained there. Main goal is to just get it painted now with the best option for the majority of building so I can do shelving and get junk on my walls. Later could do paneling if needed. Gloss grey will be good going to do a section and see how it looks. Again thanks for all the replies giving options I hadn't thought of. The building is 3600sqft with 16' walls we needed the height for some larger equipment that needs to get inside for service. Ceiling is around r30 with the two types of insulation. I wanted some sound control as I've already had some problems with the neighbor so that was another reason for added wall insulation. Also the drywall helped tremendously with the summer temps compared to previous years. But the waste oil furnace is amazing it will keep the shop as hot as I want it. This is my second season with the heater and absolutely love it. The thermostat is kept @70. The actual temp is around 68 at working height but like 90 upstairs I do want to try a couple fans in the attic and see how that works. She's thirsty but used oil for me is free. The advertised operating consumption rate is 1.5 gallons/hr @240,000 btu input. Last season before I did the extra insulation in walls and ceiling It burnt roughly 600 gallons with only the 2" insulation. This was in use from Nov. thru April. So far I have only consumed a little over 100 this season. Again I fired it up in Nov. so about 50 gallons/month I guess. All buildings are different for heating requirements and also type of oil can play a role in heater performance. Only real downside is she's high maintenance compared to natural gas. Oil filter and prescreen. The chamber and injector need cleaned monthly. Would highly recommend Morr heat in Spokane Valley, Washington if your in the market.

I am in the process of going through the same. I have OSB on the bottom 8 feet and metal above that. I am going with glossy white on the OSB and the ceiling is white. I considered gray on the metal part of the walls to break it up but ended up going white everywhere.

I researched the paint options a lot. Ended up with Sherwin Williams Pro Block primer and Sherwin Williams water based alkyd urethane. It is more durable than latex and really did not cost me much more than good latex paint would have. I ended up going through a Sherwin Williams commercial store. I needed 15 gallons of pant.

I would point out that that if you go with the metal interior liner panels, the white will be a satin white, not gloss. At least from the vendors that I had access to.

Yes, satin is good for not having to worry about cosmetic issues for the factory. For actual use it is a poor choice to keep clean.

I'd plan on getting something set up to move the air around more. That's a lot of space for a single unit mounted high and in one corner. You might run into "overheat" issues with the unit even though the temp on the floor is moderate. I have a buddy in the business and we were just talking about this problem a shop near Rathdrum (sounds like you're in the same climate zone) was having. They installed a fan blowing air from the floor up towards the back of the unit. Where is your thermostat in relation to the unit?
As for the walls....do it right now so you don't have to move all that shelving/equipment/etc to do it again in a few years. My $.02...not that I follow my own advice.

Semi-gloss walls in bright white & multi-color ceiling.

how many tags do you figure are on the ceiling Barry ?

Exactly 500.

The number was not planned, but perfect fit from wall to wall, lights to lights.

How the H E double hockey sticks do you get 500 lic plates??

I believe there was a request for them on this very board years ago. Could be wrong though, it's happened before.

Several people donated to the project, mostly when I was still in Alaska.

Their names are written on the backs with a Sharpie.

I had over 200 when I moved to PA, they went up first.

Based on the available space left, I knew I would need another 300 or so.

I bought most of the remainder at swap meets. Some I got for free from pals. A few from rusty junkers I parted out, two of them were found here in the woods at one corner of my property.