Bad video camera + little money = decent video quality
The difference in brightness outdoors compared with indoors is much greater than you'd think due to the way your brain compresses the dynamic range. If you've ever been on a location shoot that's been properly lit for video you'd see the difference - it hurts your eyes! 

I'm afraid the point here is that you're not going to recreate outdoor lighting for that price range. You are better off trying to rearrange your shooting to make the most of natural light.

If you really need to shoot indoors, getting some work lights and using hard, direct (undiffused) lighting will give you the biggest bang for buck. It's a distinctive look that can work well.