This is what I did 14 years ago and not having any knowledge about window cleaning ,I sat in front of my PC and researched everything about how to start a window cleaning business and how to build a profitable round,the way forward for me was to canvass,canvass,drop leaflets,advertise in local parish mag,all gained me customers but by far canvassing worked best for me.
I understand you have limited funds but please hear me out,when I was doing my research before starting I soon realised that the the window cleaners that were busy and were earning good money were all wfd,so I would suggest that you throw that trad gear in the bin !if your serious about building a business borrow some money for van and set up and the get canvassing.
Some guys will disagree with what I'm saying,but it worked for me .
Good luck