NO. Based on what you wrote you made (2) adjustments for the same square footage.
NO. NO. NO.
Or....am I reading this wrong?
Basically you have living space on both sides of a garage. Each has it's own exterior entry and/or you can walk through the garage into either side. That....is GLA or living space. I have appraised many homes where there is living space on each side of a garage. People built these for their parents or teenagers or many other reasons. You could call it an ADU but really........no. It's just a part of the living area on another wing. Especially since the public records show it all as GLA.
I did a SFR similar to this one. The county shows it as a SFR with 2,948 sf of GLA.
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