A sub sonic .22lr has the power to stop a fox at 100 + yards no problem.
The simple fact is to keep this humane you need to know the rifle/ammo/ballistics very well and be able to deliver the shot precisely to do that.
100 is not normally a distance to consider for fox, if you need that range, or further, then you need to consider a different tool.
no it would be more so just for rabbits. as anything bigger would do to much damage to a rabbit.
What kind off money would second hand or new cz be ??
cheers Ollie