Tripod Dolly: What to Look For
A tripod dolly is basically a wheeled platform that a tripod can be attached to which enables it to move. This movement creates a shot that is similar to the ones you would get when using a professional dolly system. They're made up of three extensions, and each one has a wheel.
The tripod connects to each end of the extensions. When it is not being used, the extensions can fold up, making it small to store and easy to transport. If you're a low budget filmmaker, then a tripod dolly is something you should own because it has the ability to create great shots and it costs anywhere from $50 to $100 to own. That's very cheap in the film world.
When buying a tripod dolly, the main thing to consider is the wheels. You want wheels that are big because small ones will be harder to move and will pick up bumps more easily. You also want wheels that have a lock on them so that you can easily grab locked off shots without needing to remove the rig.
You also want to look for a tripod dolly that has a carrying handle. This way you can easily move it around when it's not being used.