Actually quite a lot of people live in flats, not houses (and you can fit quite a lot of flats in a small space).
Of course they won't all be able to buy their own home, we've never had more than 70% owner occupation. Someone has to pay for all those rich, old, middle class peoples' buy to let mortgages
I have never suggested that we can predict immigration levels - whereas you have, repeatedly.
Spain does indeed have 50% youth unemployment, so why do you think there aren't more Spanish immigrants here? We only have slightly more Spaniards than we have Australians...
I am well aware immigration is not evenly dispersed. It is generally concentrated in urban areas where people are far less scared of immigrants because they actually know a few