Going into the sale of a business, you may want to employ the services of an accountant. They will be able to assist you with the due diligence preparation, the valuation, and get your financials in order. This will make your business more attractive to buyers.
An accountant can also work out the deal structure for you. The sales process is something that they will only be able to help you with if they already have experience in this area. If not, you may need to consider enlisting a broker to help you find a buyer.