It's the flooding problem most of all. I'm in one of the few Manhattan co-ops that still allows washing machines and dryers and it's a wonderful thing to have it in my apartment. But many landlords, co-op board and condos don't permit them because of the flooding.
A couple of my friends and I made hot ice for our school science fair. We used sodium acetate. This project won first place at my schools science fair!!! Materials: Stove. Pot. A spoon. A glass cup. and Sodium acetate (you can find it online or in certain heat packs). How to do it: You heat water in a pot and put the sodium acetate in the water.
The more ice cream that is in immediate contact with air, the faster it will melt. A lower surface area to volume ratio speeds melting because the air can share its heat energy with more of the ice cream at one time. Imagine how much easier it is to for an ice cream flake to melt than a ball of ice cream. For the ice cream to completely melt, the air has to share its heat energy with the ice cream on the surface and the ice cream on the surface has to share its heat energy with the ice cream in the interior of the flake or ball.