To answer your question: a realtor wants to make money so s/he will take all factors into account before listing your property. You can also have an independent appraisal done, but that costs you. Others have given good information, so I'll not repeat. We have sold a primary residence and a vacation home in the last 7 years. We just closed on the vacation home. It was suggested that we not accept VA or FHA loan applicants, because the government will make you raise your home to ITS specifications. Next time, I will sell, "as is." You will be amazed at what people want you to do for them, how much it costs, and how that eats into your selling price and final profit. You can say no to some things and others you have to improve. Like electrical wiring or other code items. Do interview the realtors. You are hiring them to work for you.
P.S. We are military. The VA/FHA was a decision made on a 40 year old home to help us come out with some profit after all the selling fees, federal,state & local taxes were paid.