Bought a 2nd hand tank from a dive shop near me for R1500. I also managed to find 2 extra cylinders for my cz200 hunter 1k for both(a steal). As far as mods, not really necessary for it's inetended purpose. You can get it regulated, fit a quick fill adapter, if you can find a hunter cylinder buy it. It's 30% bigger and gives about 15 shots extra per fill. It's a very accurate rifle out the box.

Best pcp to get kids into shooting in my opinion.