Pricing in michigan

I am kinda new to the window business. but have been cleaning windows for years, just not for myself. so I am wondering what is the average prices for window washing here in Michigan. I have been charging $4 per pane (for the average size double hung) inside and out. is that reasonable or is it too low? another question… when you clean residential do you clean just the pane and wipe the frame? or do you also open the window and clean the tracks. I know you clean the visible tracks but do you actually open the window and clean the tracks that are not visible when window is closed? thank you in advance!