I assumed you were plumbing in your compressed air outlets. I have my compressor in the opposite corner of my garage with 1/2" copper pipe around the top of my walls. I have 5 drops and the one in my painting corner is for painting only. My compressor is about 10 years old and passes a little oil when I run it hard. I have to have a water/oil separator to avoid fish-eyes.
I mentioned the 3/8 fittings because I was amazed how big a pressure drop you get with the HVLP guns.
We all have to fight the budget battle, especially those of us who are married,