A suspension lift over 4" gets more expensive because you need to use new arched springs in back instead of just lift blocks. Also, instalation gets more complicated because you are changing the angles of your driveline to a more severe degree. Adjustment of your axle angle with shims may be necessary. Also, you'll need some type of dropped pitman arm to keep your steering in line. A lift kit is pretty cheap and easy, but you will need a lift or a couple friends to help lift the body to install the lift blocks.