The word for the day is "verisimilitude." Sounds like "veh-rih-sih-MIHL-uh-tood" for those who haven't had the experience of hearing agent and writing instructor Donald Maass pronounce it during any of his incredible seminars. Meaning: the appearance of being true or real, the quality writers use to coax their readers into that vivid continuous dream that is fiction. Not just to render a setting with phographic-style reality, but to show how the story's characters feel about the place they inhabit. But before we, as writers, can show the characters' emotions about a place, we have to know what there is in a setting that a person could long for or long to flee from.
And despite all the help of research materials, there's nothing quite like being there to show you what it's like to be there. You can't smell YouTube; you can't feel Google against your skin. I took a break from this dreaded Week Two of NaNoWriMo to investigate a city potters' field -- a graveyard for the indigent and unknown -- for the setting of a scene. Earlier investigations included a mega church, strip club, polo match, criminal courts building, bus station. Most free or nearly so (depending on how much you drop on drinks and tips for the strippers). Every one with things I didn't expect, things I could never have found from reading a book or surfing the Net. Try looking at your story, searching for a place you can take a field trip to for that extra touch of reality. Because, while you CAN be too rich or too thin, you can never have too much verisimilitude.