Ontario Windows & Doors Pro Inc

Hello,
since my company is being accused in such actions,let me explain how this happened.
It was a semi detached in Waterloo. Two owners. First owner of this semi detached is an amazing guy,which in fact we are doing few more projects with, recomended me to his neighbour Rai. Both properties are rented out for students.
I booked installation for two days, each part of the semi per day.
When I called Raj to confirm the installation day a couple of days in advance, he asked me to change the style of one window. I told him it was too late and the windows are already made. Which is not a problem I told him. I'll put the window he wants in the production right away. It will not be ready until the day of installation. I told him it wasn't a problem as well. When installation day comes we will install all the windows except the one he wants to change the style of. Then when the window will be made we will install it when we are in the area(which was in about a week from the installation day)
I also told him he will need to pay extra for a new window and the original one we leave in his garage. He agreed.
On the day of the installation,when my crew finished,he didn't want to pay. He said he didn't have the money now. And I should come by his house at around 9pm to pick it up. Since we expect to get paid after the product is installed, I told him I will come personally at 9 and pick up the balance. Immediately he said come tomorrow not tonight! I said he's just told me tonight at 9. He responded-"I changed my mind,I can change my mind at any time I want."
I realized that something isn't right here. Especialy after he said that I promised him to make him another window free of charge. Also he was saying he was even going to hold 500$ until we install him another window. Not to mention that he held himself in a very unprofessional matter,such as interrupting and yelling when I was trying to talk some sence into him.
Since we did not get the payment for the job and the product is installed I told my crew to take my windows out. Guess what? The money was found rather fast. The only thing,my installers spent 1,5hours to waiting for him until he brings the certified cheque.
Couple of days later, he was calling me and I couldn't answer. After he called me again the next day and left a message,I called him back. I told him that he has two choises,
First choise
Since he paid for the uninstalled window and the installation of it, I could mail him a cheque for the amount that I charged him for the installation of that window.Since he kept the original window, I thought that giving him the money back for the installation of it was fair.
Second choice.
He pays 145$ for the new window and I will install it on Nov 7th

He decided that he wants the original window installed(that sits in his garage) and we are even. I agreed.
After I saw the complaint he posted(which was about 30 min ago) I called him and said that I don't want his business and I'm mailing him a cheque and he can use this money to pay to some company to install his window.
He said I lost the job at his other house.I told him that I DON'T care about his other house. He said that that was being recorded:))) I just laughed at it. Mind you it's all happened half an hour ago.
Before I saw his complaint, everything was on the schedule and his window was booked for Nov 7th to be installed.
To all of you that are considering to go with our company, you are more then welcome to check our references. Our goal is to keep our customers happy!!! For 15 years of our company's existence, this is the first case that we were going to take our windows back out.That has to tell you what kind of person we were dealing with.
First case in 15 years!!!(hopefully last)
Thanks for all of you who took their time and read this to the end.
Pavel

P.S. there was 9 windows not 6 like the customer has in his title.
So 3300$ for 9 windows is about 365$ per installed window...