I would normally only use Washing up liquid. What benefits are there from adding vinegar?
Also, I get a signature on a disclaimer for the first clean if they have not been covered as the customer will not realise the full extent of damage on the finish. Some windows are really bad when the builders have been reckless.
It would be one of the more stressful times in a persons life with work not being completed in time, budgets being stretched and the customer trying to get moved in to their new build. So you are dealing with highly strung people. BEWARE
I use the 4 inch trim 10 from unger. You do need to change the blades quite often.
If scratches on a window are visible from 10 feet or more the customer can claim. And the builder will blame you, hence the disclaimer.