Unfortunately the biggest problem with WFP is bad wfp'ers, ( we have a few on here) the guys who spend more time faffing about with nonsense than just learning how to do the job right, there are a number of areas in my neck of the woods that have also been ruined by these types.
You have a couple of options, try other areas where the WFP reputation hasn't been ruined., or try selling your cleaning guarantee better in the hope of winning back the ones who have had a bad experience with wfp'ers in the past, the third option is to take on custom using traditional methods and then convert them to wfp once they get to know and trust you, but this means still having to use a ladder for now.
It can be hard going when there are still plenty of trad guys to compete with but its still achievable.