Joe regardless of the condition of the paintwork they will still milk and spot in places,tell them that it will take a couple of cleans at least to get them half desent.If the frames are anywhere near looking like flaking don`t go near them and all this about licking your finger and seeing if it`s chalky is rubbish,in order to see whether they will come good they need to have plenty of water on them,that`s when you can see if there oxidising because it will look like you have milk in with your water.And if there sash i would use a mono brush and 1 that will go up underneath the top frame,you`ll need a square 1 that splays well,the salmon is not to good on these as the stock can get in the way of letting it splay,good luck and if in doubt don`t do it mate.