Pick up th cast iron pan and give him a good whack. Let him know this is YOUR room and you want it your way. He would not be happy if you went to his tool shed and fixed it all up your way. Let him know you want him there with you every step of the way but it has to be the way you want it. YOU will not be happy unless its the way you want it and for you to retreat there and do your work of art. Whack some sense into him and then smile and say I love you but its my room.