Suburban housing will be free in the near future.
Yes, this will happen because of lots of die offs.
However, the biggest thing is, people will not have enough money to heat such a house, even if it is free.

@brianphobos asked, why do you not get an existing house and then just upgrade it?

And, there are several reasons for why you should, and a lot more for why you shouldn't.

Passive Solar Heating

Heating will become the biggest expense for a house as we continue into this ice-age.
Passive solar heating will be extremely important.

The biggest problem with renovating an old house is, you really cannot add this feature on.
You need to design this aspect, and then build the house around it.

You can often add a sun room on the south side, but that can really get problematic for reasons like, the front door is on the south side. Or there is no real room to build on the south side. You are block off all those windows on the south side, and if that is your major cooling wind direction, that really sucks

Eave lengths and window placement are extremely important.
and these cannot be easily changed in an existing house.

Insulation

Many old house have no insulation. Meaning hollow wall cavities.
With hollow wall cavities usually comes molds and funguses, many being quite toxic to the people trying to live in the building.

If the house has been sitting vacant for too long, it is almost always the case.

So, what you usually have to do is tear off all the drywall or plaster on the inside, clean and disinfect all the cavities, and then put insulation in all the bays. Add a vapor barrier. And put up new drywall.

Now this is something a DIYer can easily handle. You can do it one room at a time.
But if you are paying someone to do this, it IS CHEAPER, to tear down the house.

A big caveat is that you are really going to want a lot more insulation than the old 2x4 framed walls can allow.
Meaning putting a layer of foam on the outside of the house... If you are redoing the inside layer and the outside layer of the house, than you have pretty much paid for an entire new house.

Windows

Those old wood windows are really pretty.... not really. Not if they haven't been maintained
And very few of them have been maintained.

Single pane windows need to be replaced with at least double pane windows.
(triple pane windows if you live in the north)

With the exterior mount replacement windows every door-door salesman sell, it really isn't that hard.
It is just you are going to have to accept that aesthetic.

So, now you have replaced the inside, outside and the windows in the house.
I am sure you are going to have to redo the roof.
Thus, you are building a new house.

Just that you are doing it in stages, without the huge price tag of doing it all at once.

And again, from my view on building houses. You start with the direction of the sun, and where you sun acquiring windows will be placed. Then work out the various wind directions of cooling breezes, and place a windows. An "In" window and and "out" window with a path for the breeze to flow through the house.

P.S. you will also want to redo the electrical.

All images in this post are my own original creations.