Running a personalized letter can help the seller understand who the home might be going to, whether that's a, growing family or maybe someone downsizing. It helps to familiarize them with the perspective buyer and I've seen homes sell for less money. Because it was going to a specific type of person.
I do recommend it to a lot of my buyers in the market today when it's when it's very, busy, very active, it can help to set your offer apart, giving yourself the best opportunity possible.