Learning Desirability Question Please

[Bee Saenz]

I know my own city extremely well, and two local counties pretty well. But how do you learn specifics of an area that isn't your home town? Ie: How do you learn if one street, (neighborhood, location, etc.) is more desirable than another? What and where do your research? What are the factors to be aware of? How do you learn what areas to avoid? If anyone knows how to learn this, I'd appreciate your help. Thank you in advance.