When Tony offers him a place at the tower, he takes it, despite the fact that life has always been tit for tat, and Tony must want something in return. Some kind of control or dominance over Clint and his life. Clint has nothing to give anymore, not that he ever did. Still, he moves in, taking with him all of his meager belongings. There’s no trinkets between Coulson and him. No photos or cards. It’s alright. It’s always been alright.
Clint could never afford to be sentimental about possessions before anyway.
Tony was pretty sure there was a ghost living out its afterlife in his kitchen. He thought it must have moved in approximately two Thursdays ago, and it seemed to really enjoying cooking - especially Italian - and crappy Chinese takeout. It also seemed to be very friendly, as it always left a note that said something along the lines of ‘for my generous host’ or ‘leftovers are Tony’s, NO ONE EAT’ on top of the food.