Of the Hancock building (inexpensive, nice, some of the best views you’ll get), eat a Chicago dog (Portillos is a good option—I’ve had better but not in downtown—plus you can get a chocolate cake shake there too), eat a Chicago pizza (giordanos), eat donuts at Do-Rite Donuts (the one on Erie is better), then just walk all that food off doing the tourist things like magnificent mile, millennium park, walk the shoreline for awhile, walk the beach if it’s still warm, walk the river walk, then go relax at Hamilton that evening.