Taurus, a big ditto on OBG. Heat rises, as well as smoke. In a real fire, the air on the ground is cooler (relative to standing upright, which may be several hundred degrees), and clearer. In fact, many FF's crawl around too while in structure fires. Don't forget to check any closed doors before you go through them.

2nd, having a good light is essential in this environment. That's a no-brainer.

3rd, no, I don't do this. I do, however, leave the lights off during late-night restroom runs. So I pretty much know how far to my restroom, and that passes 3 windows.