Shopping for cameras and optical equipment is easy and fun, so long as you know what you're looking for. Depending on the type of work you plan on doing, one camera may be far better suited for your needs than another. Before purchasing any cameras or optical equipment, do a bit of research into what type of equipment will work best for what you are trying to do. Otherwise, the possibility that you might make the wrong purchase is far too high to risk.
When not just any cameras or optical equipment will do, it's important to do as much research as possible so that you are well-versed in the differences between one type of camera or optical equipment and another.