Price of copper tubing!

I've been wanting to run copper lines in my garage for my compressor. Just haven't gotten around to it yet.
I was all ready to go and plumb it, but I have a cousin in industrial maintenance that at the time said to wait, the price of copper was coming down at the time and was really gonna plummet. Wait till it does.well, still waiting.
My compressor is a 5hp 80 gallon 2 stage upright, cuts off at 175 psi. I figured I would run up the wall from the compressor along the ceiling, down the 36' (long) side, then across 15' above the garage door to the center, and back down the center pier between the two overhead doors/ also across the back to center / with drops at front, back, 1 approx center along the long side wall, and 1 in the front corner for the blast cabinet.
I'm also looking for a deal on a refrigerated air drier at a cheap price, would be the 1st thing the air would pass thru once it leaves the air tank. I found a couple at an industrial supply place (used) for a decent price, but the cfm rating is about 60% of my compressors rated output so I'm still looking.
Related; what's the difference between cfm and scfm ratings? My unit is rated 17.some (almost 18) cfm at 175 psi. The drier I found is rated for 10 SCFM.