Successful entrepreneurs spend much of their lives building valuable companies, and ultimately, many of them end up selling those businesses. It is very common for the business to be the most valuable asset a business owner has. When selling the business, it is likely that the company will attract a higher valuation if the business owner has made the business ready for sale and is also prepared for the sales process. However, if business owners make big mistakes when selling, or their business is not ready for sale, they risk not receiving the amount of money for their business that they probably deserve, given their efforts over years and decades. If you are a business owner, we know which outcome you probably prefer, and with that in mind, here are four types of mistakes that can lower the value of your business or possibly derail a sale— along with advice on how to avoid them.1