Moving house is an extremely stressful situation for the great majority of people to have to go through, so it is easy to imagine that it is even more difficult for a cat.
A cat is territorial by nature, marking its environment by rubbing its scent over objects in the home. This is a way of letting other cats know that this is their territory, and also defines their own boundaries. When a cat is removed from its own environment and then deposited in unfamiliar surroundings, it can be quite a terrifying experience. This is particularly true if the new place has cat scents that belonged to the previous owner.
You should thoroughly clean the room into which you intend to move your cat, as making the relocation to its new home as easy as possible on the cat is your responsibility.
Anything that is out of place in its new environment can be upsetting to a cat, and moving furniture and packing boxes can frighten and confuse it. During the packing process, one room should be left until last to retain somewhere that the cat still feels at home in. The removal professionals should be informed that the cat is locked in this room and told not to open the door in case of accidentally letting it out. Put a note on the door to be extra sure.
The cat should be locked in a carrier during transit and confined to one room in the new home until the move has been completed. It may take several days for the cat to feel comfortable in its new home.