Think of the peace of mind you would have if before you start work for a new customer you could search and see what kind of experience others have had working for this individual. For example, you are about to start work for Mr. Smith on Main Street, Anytown, USA and you do a search for him. You find that the roofer, the dentist and the landscaper have all had positive experiences working for Mr. Smith and they would work for him again. You can assume you too would likely have a positive experience working for Mr. Smith. Now you can relax and just enjoy doing the work.
Or you search for Mrs. Jones on South Street in Typicaltown, USA and see the electrician and the interior designer would not work for Mrs. Jones again. This could save you lots of potential aggravation and possibly save you large amounts of money. A bad match between your services or products and a mismatched customer can be a very expensive experience.
Feel free to use this site as it suits your needs. Not only could a business owner review their customers but a subcontractor could review a general contractor, a general contractor could review subcontractors, businesses could review suppliers and other businesses. The possibilities are endless.