Every seller wants to realize as much money as possible from the sale, but a listing priced too high often eventually sells for less than market value. A property that is not clean or well maintained is a red flag for the buyer. It is an indication that there may be hidden defects that will result in increased cost of ownership. Sellers who fail to make necessary repairs, who don't spruce up the house inside and out, and fail to keep it clean and neat, chase away buyers as fast as Realtors can bring them. Buyers are poor judges of the cost of repairs, and always build in a large margin for error when offering on such a property.
Sellers are always better off doing the work themselves ahead of time.
Sellers often unwittingly spend thousands of dollars doing the wrong upgrades to their home prior to attempting to sell in the mistaken belief that they will recoup this cost. If you are upgrading your home for your personal enjoyment - fine. But if you are thinking of selling, you should be aware that only certain upgrades are cost effective. Many homeowners list with the agent who tells them the highest price. You need to choose an experienced agent with the best marketing to sell your home.