Instead of a tarp, I used to use old billboard vinyls as tarps. There are companies that resell them and they'll last forever. The last ones I did on 10x20's are still in action, and I can see them on Google Earth. Guy that bought the property hasn't taken them down in fifteen years, and they're...
Even though this is an old thread, I'm looking at doing the same thing for a small 4x4. But the material I have is a paulin cover from a military 5 ton, so it's a very heavy vinyl. I'm actually planning on stitching it for durability, and adding in ties and vinyl windows. Labor is expensive here...
I just went with some of the cheap LED 3k lumen lights from a big box store. Not too bad in a small wood shop. Ceiling height the lights are installed under is 7.5'. Seems to be a good balance, but I'll probably upgrade once these die off.