The degree of grime and allergies in your home, as well as how frequently your furniture is used, will determine how often you should undertake cleaning upholstery. However, you should have your upholstery cleaned more frequently if you have allergies or pets.
Look for a firm that has experience in cleaning upholstery and uses safe and efficient cleaning techniques when selecting upholstery cleaners. You should also inquire about the companys assurances and warranty as well.