The HC is made that the lots be assembled into a single property.
Making an HC does not require a market response.
EAs require credibility, because you are "assuming". HCs are direct statements of what your are directly imagining what has/what will, happen.
Viability or not of an HC, happens in the H&B analysis. Which, does not prevent any owner from assembling two desperate lots, as long as assemblage is legally permitted, and still allows you to appraise it, as if, the assemblage has already occurred.
And if a lender does not want the HC,
You should consult a "good" RE attorney before proceeding in a direction that favors the lender, in contrast to the appraisal "tools" you have been given, if each property is considered by a municipality as an individual property, without any regard to whom, in particular own, which or all of the individual properties.
And let's not debate the "double taxes" that would occur, if, the individual lot is being assessed by the municipality as "build able", while large lots are assessed at a lower tax rate, if they are simply considered to have "excess" land.
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