While it’s certainly possible for business owners to handle sales on their own, those that opt to do so will likely make very costly mistakes throughout the transaction process. Even if things go smoothly, the opportunity cost may be high. In the study Does Hiring M&A Advisors Matter for Private Sellers? by the Harvard School of Law several academics analyzed a sample of 4,469 acquisitions of private sellers from 1980-2012 to “examine the
decision and consequences of hiring sell-side M&A advisors.” The study showed that “private sellers receive significantly higher acquisition premiums when they retain M&A advisors” and this held true across all deal sizes. In other words, advisors generally lead to better deals than CEOs and business owners can get on their own.
You can find more information about the study on Harvard Law School Forum's website at http://corpgov.law.harvard.edu/2014/05/13/does-hiring-ma-advisers-matter-for-private-sellers/.