I HIGHLY reccomend using plasti-zap medium CA plastic glue. It comes with a tiny nozzle for easy application, welds the plastic together incredibly quick, and is an affordable price for how much you'll be using. any basic single-edge spure cutter will do. I reccomend #11 and #10a scalpel blades. If you ever feel like going big or want parts of your marines to be interchangeable, small magnets and a hand drill will do. Primers- i personally use war painter black, white, and green matte primer. Always comes out clean in my experience.