If you are presenting your product or services to a single potential client or a large group of the same, it is always a good idea to give them something to see, touch and hear that enhances their experience of why they must have what you are offering.
Audio-Visual aids can be in the form of presenting the physical product itself, showing a video of the product in use, graphics to enhance the visual, etc. At the very least, utilize some sort of interactive PowerPoint to present your product.
If you plan on displaying your product at an industry show with a booth, repeating videos of your product or service may be a wise choice. Make sure it is interesting, visual and use high definition electronics.
Budget: $500 - $3,000 per month