I was wondering how hard is it to install lowering springs by yourself. Im looking at the prokit and im liking how it changes the stance very nicely.

 

The backs are easy. The fronts require a good compressor. Your best bet is to change the shocks in the front at the same time, as the whole assembly has to be taken apart anyway. One common headache in the front is a rusted/frozen nut on the top of the shock.
Some people just remove the front shock/spring assy and take it to a shop to have it taken apart and reassembled. That would cost much less than taking the whole car in for the same work.

 

I did the fronts completely with hand tools first time. Didn't even have a bench vise to put the assembly in. Second time I bought an electric impact wrench and it was easier.

 

The Lisle McPherson Strut Compressor works great. An air impact gun saves a lot of work. Pro-Kit on a HAL shock.......