One of the things that bugs me is the "pretend to forget" brigade. It seems to be that some of the customers with access issues deliberately "forget" to leave unlocked as a way of controlling the frequency of the cleaning. I do get past some gates by leaning over on a stepladder and using a crowbar to hook around the bolt. Unfortunately, some bolts are too far down or some people padlock them.
If a job becomes the equivalent of a short notice cancellation because of no access, it can mean that the day's takings are down as it may not be possible to do a replacement job that day. OK, it may just be, say, £12. Get one of those every day and it's £60 a week - £3k a year.