Some lenders are more specific about particular properties when they are different from surrounding homes. That would be a lender-specific guideline, not an indication of all lenders. When we deal with properties that are original or abnormal from porperties that could normally be used as comps, we order our appraisals through national vendors and the underwriters give them more leniency to go outside normal property limitations for comps.
To be honest, the simplest thing you may need to do is switch lenders. An appraisal can be done - you just need to find the lender that will order it and honor the value.
If you have any questions or if I can be of any assistance, please let me know.
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