There are a lot of systems out there, Ionics, tucker, concept. Check out thier web sites.
Traditional v WFP. if you are doing builders cleans you will probably need both as wfp will not take of tape, labels etc.
Trade.. as far as I am aware no one owns a patch, if you buy a round you are buying the goodwill not the ground and the goodwill is maintained by the standard of your service delivery. Besides we work in a free market so you just need the advertise your service.
If you are running window cleaning as a seperate entity make sure you have a fully trained op. There are courses available,
Good luck