Tough decision

We are looking at a colonial (house # 117) listed at $300K. 1600+ sq ft, 3 BR, 1.5 BA, oversized 1 car detached, no EIK, each BR has a closet and there is a coat closet by entryway, no linen closet. We do not want to offer more than $250K and I'll explain why. We are concerned it might not even appraise for $250K. It is move in ready with the exception of the roof needing to be replaced soon. Very nicely kept. Our reservation comes from a house deal just a few houses down that we were involved in and fell through due to a low appraisal. That was in September. That house was a unique cape cod (house # 127), 1800+ sq ft, 3 BR, 2 BA, 2 car attached, EIK. I'm only pointing out main differences, that I predict would affect appraisal outcomes. 127 was not cared for as well as 117. It definitely needed more work, but we loved it. Our offer on this house was $250K. We went through the entire process; inspections, appraisal, title search, etc. The appraisal came back, $210K. I attribute some of the failure to poor representation, some to us loving the house and rushing into a deal without researching more. Now my opinion is, with the differences I listed in these two properties, 117 shouldn't appraise for much more than 127. Which sways me to want to offer low 2's. Am I relying too much on 127's appraisal? Does anyone else have any opinions based on what i have described?