Hi I have 2 X Walther co2 pistols,these can be found for not much more than a compact there's a cp2 on guntrader for £250....a brand new fire extinguisher is about £23 delivered not too expensive ,they usually come with the filler cap but they are about £30 on e gun.
The grips are better on the later ones (cpm1 my fav) also have an early CP 2 and the diff is the grips,
Not used a fwb yet so can't comment on them..my next step is to join a club and if I get as far as comps then I might treat myself to a new one...
Try an ask on here if something takes your fancy,that's worked for me !
Cheers ian