I had my two cars rustproofed by myself last fall, now it's time to do it again, it is very easy.
I bought 4 litres of Krown T-40 rust proof agent, then just used a spray gun and an air compressor, sprayed my cars on my driveway. I took me 1.5 hour to do 2 cars, I used only half of the T-40 that I bought, a goggle and a respirator were necessary, 2 jack stands and 2 ramps were used to raise the car.
There was some dripping, it's not a big deal since I covered driveway with some card board.
99 BMW 540i 6-speed 110K Km
03 SAAB 9-5 wagon 80K Km
92 400E (Sold) 245K km
Still missing the days with the Benz, it kept me busy.