a body lift raises the body by placing spacers where the body mounts to the frame. I think the largest you can get is 3 inches. You NEVER want to stack the spacers any higher than that. it places way to much stress on the body mounts and bolts. an actual suspension lift raises the frame and body together away from the axles. That is about the most basic definition. Using drop brackets and bigger subframes, taller springs, spacers or taller coil overs. There are different ways to go about it. The reason for the difference in price is you get what yo pay for. I would say a Fabtech kit would be a higher quality kit. I think they started making suspension parts for the dessert off road crowd. So their stuff can take a beating. Some other good kits I have used in the past on my vehicles are Rancho and Shyjacker. If you are looking to get one for your truck that is where I would start to look.It is like anything else you get what you pay for.