You won’t be able to go the super cheap route of using a camera for the tracking because clear setups don’t have a diffuser to resolve the blobs of the user’s interaction. Thus you will need to use either projected capacitive films (same tech as on smartphones) or use an Infrared Touch Frame (cheaper). The clear projection film is easy to acquire too. So, all you need is the following:
Holographic Rear Projection Film
We sell the first two and the other ones you may already have.