I can't speak for the USA, but in Europe were space is very dense in highly populated areas you just buy small real-estate on good/acceptable locations that you rent out. Try to get as many as you can in your life.
When you retire you hopefully have a few of them around paying for your lifestyle. In Europe the rent will never cover the loan you have to carry on the real estate, but that's why you should add money every month to it, because when the loan is payed it's the best retirement fund you will have.
People will always rent apartments and houses at good locations, if you are not dreaming and putting the price right.
That's my retirement plan.
The cash is for fun and to buy the fun stuff. I never sell real-estate I wan't to keep.
Yet another problem caused by the boom & bust fiat money cycle.
The illusory booms fool everyone into thinking they are wealthy and well-prepared for the future, and that their houses & portfolios are going to keep going up in value forever. They're also fooled into thinking that government spending & borrowing can just keep going up forever with no consequences. Then the inevitable bust sets in and the illusory fiat wealth disappears. To add insult to injury, taxes and/or inflation (another type of tax) then have to go way up in order to either pay interest on the debt or slowly default on the debt through inflation.