Well it's already put in, I think he earned his $280 for the install because it may have been a simply layout but putting tack strip into cement (120 feet) is not easy and getting the carpet in the basement was not easy either. I didn't waste my money on the moisture barrier pad, the "moisture barrier" is just a fancy word so they can charge more money. But HD did have a good price on it. I hope you bought the pad yourself and didn't get it thur the HD carpet quote. When I got the quote from HD after they measured (free) the pad was $300 on the quote, I priced the same pad they had in the store and it was only $180. So they pad (pun intended ;-) the price of the pad to help with the "free" install.
When we picked up the carpet it did take about 45 minutes...and I drove there earlier that day to make sure it was really there because Ive heard horror stories about big box stores saying that the carpet is in and its not. I told them to have it ready for us to pick up at a certain time and it still took some time. But I didn't mind because I saved a lot of money buy buying at a big box store.
Oh, I hope you got 8lb rebond....the thickness doesn't mean it's going to last longer. We used 3/8 inch 8lb rebond, I didn't want too thick of a pad in a basement.