According to this RedFin data from 2019 -- which looked at normalized sale prices and Walk Scores above 50 -- it is about 23.5% or $77,668 for 16 major US metro areas. Again, this is 2019 data and so things may have changed a bit, especially with the whole COVID thing.

It also varies by metro area in this data set. The premium in Boston, for example, is almost 30%. Whereas the premium in Oakland is actually a slight discount (-1.3%). There are going to be local conditions that play a role.

But as a whole there is an economic trend here that makes intuitive sense to me. Though it's not just a question of how pricey your home is. You also need to consider your transportation costs, the value of your time, and the health benefits of living in an environment that promotes consistent and moderate activity.

When you factor all of these things, maybe "premium" isn't the right way to look at this.