Best Lighting Options

I'm shooting a documentary, a bit of walk around but mainly most of the people will be sitting, I'm on a strict budget, I only have around $500 or so to play with lights, thats including everything beyond lights as well. Any idea on what set up we should do, something that wont be to hot or to complicated, also slight portability plays a factor.

Documentary of what? I would assume some sort of event if people will not be bothered with you putting a light on them.
What you're shooting, your budget, and desire for portability all go hand in hand with what could be best recommended.

LEDs are light weight, portable, pretty durable considering, and CAN be inexpensive.

Is renting out of the question?