I run a hosting business on the side of my on site support business and the thing is the password policies you have there are a little too much for customers as 3/4 of them are absolute retards or just don't have the time to do think about such things.

My trick was to create a global password that if the customer is literally too retarded to get it through to that i would give them the global one and send it to them in either sms or email so they have a copy at all times.

Other than that the second resort is my remote support applications i have developed which i would make them send me a request and then i would open notepad and make them type the password they want in there so i could see it, and then once they have it correct save it on their desktop and then put it in the pw change.
-Also business support calls feel free to slug them $60-70 p/h for remote support unless they are on a paid contract.

Last thing you want is a customer taking up phone time with stupid questions its easier for 4-5 mins of remote support rather than 20-40 minutes of retarded questions.