The MLS (Multiple Listing Service) is a cooperative listing service used by licensed real estate agents and brokers. Members of the MLS input detailed information into a database regarding properties listed for sale. All members of the MLS have a right to show or sell a property listed on the MLS. The vast majority of home sales are made through participation in the MLS.
Your goal should be to have the most potential exposure to your property. That happens through the MLS. Real estate agents consider the MLS as the go-to inventory of homes and use it to locate properties for their clients. They rarely use newspaper ads or other advertising sources to locate available properties, even though they may use them for their own advertising.
Having your property listed in the MLS will provide needed exposure and will increase the chances that a real estate agent will find a buyer for your home.