For Sale by Owner (FSBO) is a method of selling a business without the use of a business broker.
Small business owners may employ online listing/advertising services to market their own business but do not pay a commission and represent themselves without the help of a business broker throughout the sale.
It is more of a DIY type of sell where the owner has the control over where listings go, what offers they accept, and how much they ultimately ask for and receive for the sale.