Buy your brush and compressor across the NET. Local retail is expensive. You can also buy artist paints in a tube, the mixer(diff grades of it allows paint to adhere to diff surfaces) and mix with water and have a lot of paint cheaply. I bought white and will try it for the next undercoat.
small grit sandpaper bought at home depot, lots of little things around the house you throw away make nice modeling stuff. The mylar in my cookie box is going into the landing lights, some thin speaker wire is doing brake lines and bomb connects. Medicine bottles or those little plastic pill holders the hospitals use hold paints and clean easily. Popsicyle sticks make nice spreaders, any flat piece of somthing. A carboard box with sides cut out makes a nice Acrylic paint shed. Always look for a make do before you drop money that could go on something else.
HC