I know this doesn’t answer your question, but: (just my opinion)
Cold calling is a waste of your time. Don’t worry about industries or categories or types of business or whatever.
Get out of your house and personally look for dirty windows. If you see a business that has dirty windows, give them a prepared quote. You can’t know if a business needs window cleaning over the phone.
Get out there and “hit the pavement”. I sincerely doubt anyone built a commercial window cleaning route over the phone. I may be wrong, but in my experience the optimal way to build a route is this:
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Go out and look for dirty windows
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Quote those businesses
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Repeat until you have enough work that you no longer have time to canvass.
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Profit.
Hope that helps.