POA is a tricky subject. i can only assume youre talking about a special POA that limits you from only doing this one thing in his name. if he is stupid enough to give you unlimited POA then you can do anything in his name. buy a house, open 12 credit cards, empty his bank accounts etc... if it was you giving out your POA i would tell you to be careful, but since its the other guy, well...good luck.