A building inspection should be used to identify things to identify things are urgent matters that need to be fixed, potential safety issues down the road and learn how the systems of the house work. If there are serious issues with the house, I can understand why you can use that as a reason to walk away from the house.
You can not use a building inspection as a negotiating tool to drop the price of the house substantially unless there are major items wrong with the house. If you feel you are paying too much for the house, we can see what appraiser thinks that house is worth when they come out for the bank. I always have my offers contingent on satisfactory appraisal.
For any things that needed attention, we can negotiate repairs by either having the owner fix them, have them drop the price based on estimates for work or offer a credit toward closing costs based on the estimates of the work.