Prices vary from area to area and what you feel your worth is, pricing can be tricky in the early days because you haven't had the experience to know how long things will take.
My advice is never price cheap, once cheap you'll always be cheap and when you try to raise your prices customers will create merry hell.
Your job is a one off/bespoke clean and as such carry a premium over what you can make p/h on simple straightforward glass work.
You will always get people screw up a face, look shocked, gasp etc... But if it's a days work then you need to charge at least a days money if not more. You will have others that simply snap your hand off its swings and roundabouts.
So in short if the job is 8 hrs work. 8 x hourly rate minimum.
Personally From the loose description your well under on price vs effort/time
Darran