rear bumper smoothing and lowering 3 door stilo

[dcfcsince90]

hi everyone,

i am looking at doing lots of different things to my stilo. its a 3 door, 1.6 in yellow. i have already changed a few things and i am now looking at lowering it by about 30-40mm and getting the rear bumper smoothed, possibly the boot as well. iv had a quick look around but was just wondering if anyone knows how much it costs to lower it and how much the smoothing will cost approx. any tips will also be appreciated.

cheers aaron