What on earth did window cleaners do before mobile phones? 
We never text, never have cancellations and never have access issues as all vans carry ladders for access purposes. Happy days. If gaining access with ladders is too difficult they simply get the fronts done and the backs cleaned at a premium rate if you catch them in. I like it simple. 
Unfortunately Dave WFP has brought us a new generation of shiners intent on making a simple hassle free way of making
a living as difficult as possible.
Er, how is sending a text more hassle than getting off ladders to get over a gate.
The problems the above people have is with the customers, not the gates. 
Cant really argue which is handier but put it this way how often do you get guys who get over gates and don't text experiencing
the above problems.
I had the same problem with customers when starting out so I know the annoyance involved, but not once did I blame the customer
as I know how easy it is to be forgetful. ( it didn't stop me calling them the odd swear word under my breath )
To be honest with the amount of specialist ladders now available its not hard to get over a gate easily, quickly and safely its
just pig headedness and lack of competition that stops some from even trying.
