Here is the site for hiring projectors. I found this site in a video mapping tutorial website. The common thing I read in tutorials is that if it is my first time working with video mapping I should use a small projector. They say that after finishing that I should want to go bigger. So this site will be helpful even though I will not rent it from here I can get information of different types of projectors and what they are used for.
What is the difference between a short throw and long throw lens? What are zoom lenses?
When there is no option of placing a projector at a small distance, the long throw lens projector is used. It helps casting smaller, better defined pictures from big distances. These images which would be too large if a regular lens was used. The long throw lenses are usually used in large venues where there is no opportunity to mount projectors closer to the screen because of architectural constraints, for example, in churches, or stage performances, concerts, etc.
Most projector lenses, either standard, short or long throw come embedded with the zoom option. The feature operates as on usual cameras and allows creating a larger or a smaller image without moving the projector.
Source: 3d Video Mapping Projection Tutorial | Weltlighting.com