A comprehensive exit strategy boils down to a simple mathematical model we call the value equation.
The further the business is into its organizational development journey, or higher the business is on what we call the five steps to freedom, the higher the multiple of earnings the business will fetch at the time of sale.

So the market value of your business is largely determined by what step the business is in.
Here’s the key to building a business to sell.
The value equation is simple, but it takes years to build. Start early, move your business up the steps, and make it less dependent on you. For more on this, have a read of the 5 steps to freedom for business owners. There is also a general page on exit strategy on Wikipedia.