Newly built homes and DADUs in West Seattle consistently appraise between $600,000 and $725,000, with higher valuations for modern finishes, efficient layouts, and private outdoor space. Your planned two-story design aligns closely with what buyers and appraisers reward: new construction, functional layouts, and low-maintenance living. Based on these comparable homes, your completed new home is expected to appraise in the $600,000 to $650,000 range.