When the county appraiser has the wrong # of rooms for a house

[Bienes Raices]

Usually when this happens in my area, it's because the current owner did an unpermitted garage conversion, but sometimes I see houses where the information is just wrong for no apparent reason (always less rooms than the real number).

Can this come back to bite you when you sell the house? And can the county come after you for back property taxes if they find out there's an "extra" room they didn't know about for years? Is it a good idea to let the county know that they have the wrong information in their system? thanks