Help with quote

Residential cleaner here, but I recently relocated to a smaller, isolated area. Been asked to price a storefront. There is not enough business in this small town for any kind of route. So no way I am going to go do this for normal store pricing in a City. Most ground work is done the janitoral companies. So I need your help! If they say no, that’s fine. What do you think would be fair for both parties?

24 panes total including two doors (double door) and two single inner doors which open automatically.

One off price to do it all inside and out (they would probably go for quarterly)?

Outside only (just the front 10 panes and the two outside doors monthly)?

I have been told to charge $2 bucks a pane for commercial work but not sure. I would be interested in what the price others would charge for the Canadian market