We recently had new carpets installed in two bedrooms and the living room of our condo prior to selling it, and decided to go with Home Depot as they had a deal where the install is only $199, no matter how many rooms there are!
The salesperson was decent, but it was the installers that shined for me! They were very professional and efficient. The condo was a tight space and they even helped us move a couple of pieces of furniture.
If you're doing multiple rooms at a time, it's definitely worth waiting for the $199 promotion! A great price for a great install experience.