I would be aware that if the concrete doesn't have really good consistency it may act like untreated wood. Perhaps there is a conditioner to be applied first. I've ruined enough porous things trying to do it without conditioner. But if we are talking about it I'm sure it exist! Hopefully easy on...
Very nice looking shop. I ended up in here looking at how you loaded/unloaded the mill. Do those trailers lower to the ground? Then raise up to haul around? Looks like the tractor was of great help unloading. My driveway has a very slight grade to it. But I'm wondering if I can build a 4x4...