An individual received an MCD property tax notice that included a mezzanine floor added in 2022, but assessed retroactively from 2004. The property was purchased in 2012, and this area was not mentioned in previous notices. The advice given is to pay the minimum tax to avoid penalties, formally reply to the MCD with supporting documents, and appeal to the Director of MCDs. If unresolved, further appeals can be made to the taxation appellate tribunal or through judicial review.