Research your future purchase
Considering the often hefty price tag on even the most basic of projectors many people choose to purchase used projectors for what may be a fraction of the price. As with buying any item second hand there are many benefits to be gained as well as many risks to be taken.
It is of the utmost importance that you do your research thoroughly and find out the pitfalls inherent to your future purchase. There are many ways in which it is possible to do this. You could locate copies (back copies preferably if you are interested in used projectors or older models) of projector related publications such as The Home Theater Magazine (www.hometheatermag.com) and Widescreen Review (www.widescreenreview.com). These magazines and their respective websites hold lots of useful information, projector reviews and discussions about projectors, home theater, and all related equipment.
As with buying a brand new projector it is important to know for exactly what purpose you require it. You need to consider both dimensions of the space and the brightness of the ambient light as both these will greatly effect your choice of projector. Whilst not as bright as other projection the CRT (Cathode Ray Tube) system provides the clearest picture but are very expensive and bulky. The more common (and affordable) are the LCD projectors (Liquid Crystal Display) and DLP projectors (Digital Light Processing) which vary in size from as little as around 3-4lbs up to large projectors suitable for use in halls and auditoriums.
Warranty or Guarantee's
In terms of buying used projectors of any sort there are a few things that you should check. Check for some kind of warranty or guarantee, most suppliers will provide some kind of warranty depending on the age and condition. Check to make sure that the projector has been suitably tested for both safety and general working condition.