Change the roof on a BRRRR?

[Joe S.]

One author recommends replacing the roof on houses that you are going to BRRRR. The logic behind this is that the appraiser will give more value to the home and you have just affectively financed a new roof. If that happened on a regular basis I can see how that logic would be solid. On the other hand there are a lot of appraisers that are simply going off comparable sales square footage etc. So let's say your roof had 10 more years left on it easy and you changed it before the refinance and the appraiser did not raise the value of the property due to the new roof. In a case like that I do not see the benefit of changing a roof that still has life left in it. What are your thoughts or experiences with changing roofs in hopes of having a higher appraisal?