I charge more for 2nd level windows but not much. I keep it simple and just add $1.00 over my 1st level window price. I use a WFP almost exclusively on residential but the 2nd and 3rd level windows are the main reason I use WFP. It cost more to use a WFP than a one time purchase of an extension ladder so that’s how I justify adding the small charge even if I don’t spend the extra time and risk laddering up for 2nd or 3rd story windows.
I do on site price quotes only. If I’m going to have to deal with extra time and hassle on any given window whether it be 1st or 3rd level I’m going to make sure I’m getting paid for it. The price quote my customer sees is for the entire job, not broken down per window or laddering up charges.
The way I see it, the 2nd and 3rd story windows cost more to clean. Therefore I charge a tad more for them.