I have been traditionally cleaning the windows and doors on this property for about 1 year, outside and inside.
On one of the inside double glazed units there are some scratches that I have not noticed before.
The customer has not said anything.
I clean the outside first and then for the inside I change the water, rinse the mop, clean cloths and clean microfibre.
I never use anything else or other tools such as a scraper.
I am sure if there is dirt on the applicator or microfibre this coud cause a scratch on the glass but can a clean microfibre cloth scratch glass?