It only cost me $60 to do my car ($20x3 gallons). I was installing a fan that has those plastic tabs that go through the radiator at the same time, so my radiator was out anyway. I flushed the whole system with water for a good long time, then blew it out with air from a compressor, then ran a vacumn through it for a few more minutes to be sure it was bone dry in there. I also modified my radiator cap, removed the spring and bottom seal. The system now runs on 0 pressure, and works great.