Appraising Guest Home on Property

[Chris Carrigan]

I have a 26 acre luxury equestrian property under contract for my buyer. We just got the appraisal back and it's very low because the property has a second home that is just as nice as the main home - 4000 sqft. The appraiser is saying that home is functionally obsolete and basically giving it no value. If this home was appraised on its own with just an acre of land it would have a market value of close to $1m, but because it is considered an accessory dwelling and obsolete they are giving only an $80k adjustment. The home would make an excellent STR, but the current owners only used it as a guest house so there is no rental history. Has anyone dealt with something like this before and have a strategy for appealing that appraisal (We are waiting on a second appraisal from another company). They can't subdivide it out due to restrictive covenants.