CARMAX Alarm system installation failed + big liar and miss communication between the divisions. Kennesaw, Georgia

I purchased car from this CARMAX. Sales person was very nice and kind I have ever seen before. I decided to purchase the car within the first visit. He told me to install some security system and this price will added to finance to my account. That was very smooth operation for this process, Still nice. However I had to make a schedule for the installation of security system but mechanic division was not open on sat and sun. So I have to use my pay vacation from my company that I used to work to get a car security system. After they installed my security system I was pretty happy I feel safe to leave my car on parking lot. I was figuring out for better security feature on user's manual, It is said this package comes with siren tone speaker but it looks like they forgot to install for siren device in to my car. Now here is they made the but choice, I call to the car alarm system manufacture by giving them what I got from CARMAX and they told me it should comes with siren tones and everything listed on user's manual. My security system was missing siren tone device.So I had to call to sales person to make sure if there is missing parts what I purchase from you at mechanic division twice, But I never had respond from that sales guy. Now I had make a call to mechanic service front desk and she told me they can fix this issue this problem since mechanic man did not install proper way. So I made another pay vacation which is I'm not supposed to taking off that day. My manager was pretty pissed off on me and the CARMAX as well. I was on the way to CARMAX and mechanic division front desk told me schedule is cancelled ... I was like what happen? She told me mechanic person had to go home because one of his family had car accident so it was emergency that I understand very well. But I was pissed off when she said "You have to make another schedule on next week." I was totally speech less. Because they did not install system proper way and it is not working proper way. I totally disagree with her suggestion that time. She was trying to hangup on my call because she wants to run away or something else. I knew that is going to happen. I asked her there is several person can install the system proper way but she said no I pissed off twice and I had to hang up and call back to store manager(useless manager ever seen before). Since I was disagree with her opinion I told store manager to returning my security system at no labor charge.She was nicer than mechanic division front desk service lady.Of course she supposed to be nicer than every person in that store!! Finally she said will going to investigate first and return the call as soon as possible but I didn't get the call at same day.. Next day I received call from store manager and I was told that security system installation KIT does not come with siren tone device. OK now I told her I call to car security manufacture they told me it comes with everything. After several conversation she will going to have another investigation which is not necessary but she wasn't trust me at all.I think she was explained by mechanic person (LIAR) that is not comes with siren tone sound.Finally she call me back and she was explained they will allow to return my system with labor charges on it...... I was like with what!? My brain was blowing off that time.Finally one of my friend decided to help me out by contacting to CARMAX headquarter. I think it was south regions manager who is take care of entire CARMAX in southeast USA. I explained entire story again and again he seems to very upset about THAT BRANCH have hired several useless employee and not enough trained for communicate operations. After several minutes I got so many apologize call from who has involved this situation but I was not happy at all. They involved one my friend and my co-workers also I spent my 2 days of pay vacations + entire of my schedule was messed up. They said one of CARMAX mechanic person will visit to my working place to install proper way he did good job. And they give me money back entire money I spent for the system included labor charge. It's about more that $300 After that I got a call from store manager the person who did install my alarm system he was fired. Of course that is going to happen I thought so...One small thing fail will become huge problem. I will never going back to them NEVER!! Be cause mechanic service operation schedules are very inconvenience to me. I am not part time worker, I am full time worker!! Who want's to take the day off during the weekday just for the fixing the car? They should think about reschedule for regular full time worker!! I will purchase my car next time from authorized dealer they should open on SAT for mechanic service such a TOYOYA or HONDA.