I got lucky, my company was giving them away to avoid having to pay the annual inspection fees, where they were being kept they were not required. Anyway, all I had to do was sighn a waiver and they were mine. They are all large Ansul industrial ABC type (a few very large CO2), most brand new and still in a box. I think I counted about 70-75 of them. Yeah, I think I am set. I also gave about 10 to neighbors.
The reason I took so many besides they were free is that I live in a rural area with no fire hydrants, just a pump truck. I figured this would better my odd a bit. I have 3-4 on each story of our house including the basement, rest are in the barn.
...they emptied and threw away even more than that and gave tons to the local fire dept.