>>My front door (where deliveries usually arrive apart from Santa) is about 4 inches off the ground and about 7 foot high so at some point that drone is going to have to come down. Also most new build in urban areas is flats.

Lets hope that Amazon thought of that. ;-)

>>its a moot point. Whats the future model for where we live . is it very high density urban. (no transport necessary beyond mass transit systems) or dispersed.

My anecdote is that average house price in Auckland City now exceeds London prices. Auckland may be a nice place to live but the biggest reason is shortage of land as the city tries to limit its expansion. It's the cost of fixed transport like rail and roads and other underground utilities that drives the need to intensify: remove the reliance on fixed transport or the need to travel to town for work, and the concept of built-up cities is less relevant. You can live where you like. FWIW I'm seeing that a lot in placed like Devon where a lot of doctors I worked with last century, have moved right out of the city to smaller towns or hamlets. They brave longer transport times so they can escape the hurly burly. I think a lot of people would be delighted to do the same if not for the tyranny of distance imposed by clogged fixed transport that costs a fortune to expand.