I would not discount, or mark down, a listing price on a home just because the style is contemporary. It may take longer to sell but this is true of many homes that lean strongly towards a particular style and away from neutral.
Yes, in general contemporary homes are less valuable in New England than more traditional styles like capes & colonials . All else being equal (location size, amenities, condition), maybe 10-15%. Its hard to nail down. Location & Condition have the most significant impact on value in this market.
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