All installers i have ever employed charge a furniture moving fee.
Will Carpet Installers Move Furniture. Sounds like your grandparents went to the cheap store that cut the price by not moving the furniture. They also charge a take up and disposal fee of the old carpet.
Furniture Moving For Flooring Installation from doverfloorcovering.com
I would make an exception say for a mover if they managed to maneuver a big piece of furniture through an awkward corridor or up the stairs do you have any really heavy furniture that they would need to move to install the carpet? Please do not try to help, which one of my customers did one time. Homeadvisor's carpet installation cost guide gives average carpet prices by type and style.
Tip the installer if they had done any extra job like heavy furniture shifting.
They can help you estimate carpet installation prices so you can manage carpet installation costs. Their judgment is called upon to evaluate the underlying flooring for imperfections. Calculate new carpeting costs per square foot to average cost of putting carpeting in a living room. Their tv commercials advertise free or almost free carpet and flooring installations if you buy a certain amount of flooring materials.