I am a stickler for location authenticity, so I either write about places I know well, or spend far too long on Google earth and Street View getting a better picture of what the character would see if standing in a certain spot. I am also a strong believer in getting professionals to help. People love being asked about their workplace activity. In my novel I have a fight in the cockpit of a plane and I got some very useful input from various pilots about things like how the combatants bodies would place themselves in such a confined space. One of them said think of it 'like having a knife fight in a telephone box'. That image got me exactly where I needed to be!