The Las Vegas housing boom of the mid-2000s ended in 2007 when residential building just stopped cold. Up until then, it was all go, and they crammed as many residences into an acre as they could.
Not all the neighborhoods are this dense, but that's the way they were headed. In many states, these would be considered patio homes, essentially free-standing condos, but in 2004 Las Vegas, these were single-family homes. Really ugly. In the sense that the recession slowed down this kind of rampant growth, it was a good thing.