does it cost a lot to make a "gated community"?

I don’t know about where you live, but I’ve never, ever seen an upscale gated community ringed with razor wire. I would think it’d be considered rather gauche.

The trailer park next to my neighborhood is almost a gated community. It has a wall all the way around it. It’s only missing gates and guards.

In Mexico, lots and lots of middle-class people live in proper gated communities. Heck, I’ve lived in Mexican gated communities. It’s usually a legitimate security issue in Mexico, though.

Bin Laden lived in a gated community for all the good that did him.