Food, clean water, sanitation, medicine, petrol, and other goods/services will be cut off from their first. They will suffer the hardest. Plus there will be lockdowns (ala Shanghai). It'll be like Mad Max on steroids.
Having a house and land out in more rural areas is one's best bet for long term survival.
I know people who have plans for if/when major metropolitan collapse leads to people flooding out into surrounding areas. Mad Max it is.