The idea is that real estate for parking will be scarce in the future, so the Metromorph will go vertical up the side of your building and park outside your apartment, at which point it becomes a balcony. This is where the Transformers bit comes in, though we admit transforming into a balcony isn't likely to scare Megatron into a quivering mass of mechanized steel. Nevertheless, the Metromorph will save the humans by freeing up parking spaces for other uses, like a quidditch stadium or whatever else becomes the national past time in the future.