Umbria can either be a great street or a tough street to live on depending on your goals. If you're looking for accessibility, walk-ability, and an active neighborhood, this is a great street to live on. If you're looking for extra parking, have no interest in the train, or don't frequent Main St. in Manayunk, you might end up paying more for something you don't really want or need.
As stated already below, having more properties for sale in a small area can help you negotiate a fair price; if supply goes up, demand goes down. I actually live right down the street from Umbria and have nothing but good things to say about the location, the neighborhood, and the people.
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