You didn't give examples for #1, but it describes NoDak and Wyoming near oil and gas finds.
#2 is classic NYC, SF, and the like.
Luanda and Moscow are in different countries. And neither is all that expensive if you're a native (neither is Tokyo); they're really expensive for expats. The most expensive cities in the world are the ones that artificially limit housing supply with mandated sprawl development laws. Those cities like SF and NYC are mostly in the USA.
#2 is classic NYC, SF, and the like.
Luanda and Moscow are in different countries. And neither is all that expensive if you're a native (neither is Tokyo); they're really expensive for expats. The most expensive cities in the world are the ones that artificially limit housing supply with mandated sprawl development laws. Those cities like SF and NYC are mostly in the USA.