It was more common for people to build from kits awhile ago.
To buy a piece of land to build on, order a house kit from a catalog.
The home kit would be delivered by railroad car.
It was the buyer who had to arrange moving the materials from the railroad car to the build site.
It would take a large truck and people to load and unload it. They did not always plan on that part of the expense.
There was a limited amount of time to off-load it from the railroad car.
If the truck broke down or no one could be found to move it, they built near where it was delivered.
Near the railroad tracks.
The "low rent district."