If you have villains, baddies, or just general antagonists in your story, then presumably they have to live somewhere. Or, if not live, at least show up somewhere for your heroes to interact with them. But where? After all, piranha filled volcanoes aren’t that easy to get hold of these days.
Actually, that’s sort of the first point, which is that the location should be appropriate for the individual concerned. That should be true in both practical and symbolic terms. The practical ones are “could this character get hold of this location or show up in it?” A slightly miserly neighbour, for example, is not going to have his own Tower of Doom (unless he’s been watching the pennies to save for it) but he might have a bungalow. A firm of accountants probably wouldn’t work out of a magical world (unless they were were-accountants, forced to do tax returns every full moon), but they might work out of a block of Georgian offices.
Notice that they’re specifically Georgian offices. Now, what about if they worked out of modern glass fronted ones, or an office above a shop? Don’t those things immediately tell you something about the accountants concerned? The same should be true of the locations you pick for your antagonists. I’m not necessarily saying that their home should look like it belongs to the Addams Family, but it should always say something about them.
Sometimes, of course, what it says is that they’re very good at fitting in. The villain who lives in a sweet little house just like the hero’s can be an interesting trope too.