Would not dream of putting a wooden floor in the kitchen, for the simple reason that they scratch very easliy with furniture being pulled across it, no matter how careful you are. As for putting timber floor in a w/c you could assume that there will be water spilt on it from time to time thus eventually causing either the floor to warp or rot, there some very good heavy duty linos that have a timber effect and would be a lot more practical for a w/c. You can not beat a timber floor in a sitting room, but you need to be careful as they are easily scratched even with protectors on the legs of any furniture that might be in there, as for price you can spend as much or as little as you like, but do not attempt to put pine down as it is very soft and the legs of chaurs will mark it.