I'm not sure where you had in mind for the location of an inline lubricator, but keep in mind that anything after the lubricator such as a hose section will be contaminated. It's safer to put a drop of oil in a tool periodically. The inline "filter" is a good idea.
Many, many years ago I painted a number of cars with a small compressor, similar to the twin piston I mentioned. It takes a lot of prep to overcome its shortcomings. I used three inline filters connected together on a belt behind my back. A four foot hose connected to the spray gun. Air filters(intake air) are a problem with these small compressors. They are too small and clog easily. I made up an adapter to connect a four inch flex hose to a remote mounted ten inch car air filter. Actually all compressors have filters that are too small . I have that same setup on my big compressor now.
You have to paint with the compressor is as cool as possible. That means all clean up of garage and car has to be done the evening before and then shoot early.
It's a good idea to use the moisture filters for any sander if you're using them for very long.
Painting lawn chairs is not the same as painting a truck. Wait till you've painted the inside of the bed on that 3/4 ton. You'll think you just painted 20 lawn chairs and wonder why you didn't buy enough paint for the rest of the truck. HA, HA
About the capacity and life expectancy of that oilless compressor. Are you going to listen to that tool "expert" at Sears or the other guys here that said they've been there and regretted it.
I would run three 220 lines to the garage. One to split off for extra 110 outlets, unless you already have a sufficient amount now. One 220 for a welder. If you were to get a real compressor, it has to be hard wired. It will also need a fused switch and a mag starter. Have the electrician run flex conduit and pull the wires later, when you need them.
