s vagina, rectum, or mouth), or overt exchange of blood as can occur through shared injection
equipment. Exposure to blood in the environment, hand shaking, shared toilets, etc, etc never transmit HIV. Based on those principles, responding only to the title of your question, you are not likely to be at risk for HIV in any way related to the window cleaner, unless you had sex or shared drug injection equipment with him.
Now I have read the question itself.