You don't need to spend any money to have some handy reflectors. All you need is cardboard and tape. Take two white cardboard, foamcores or any other white thing that is somewhat thick and tape them together.
You can use them for reflectors or backdrops. I often use them for food photography when I want to open up the shadows. If you want even more versatility, get a foam core that is white on one side and black on the other. Here are some examples.