The jonghapbudongsansae exclusion filing window runs just 15 days, from September 16 to 30. Missing two qualifying rental units can push the bill from 300,000 won to 4.2 million on 2 billion won of assessed value.
A single-home household pays no jongbuse (comprehensive real estate holding tax) below 1.2 billion won in assessed value, and only 60% of the excess enters the tax base. A 2bn-won home computes to 2.76 million won. Every step calculated.
Jongbuse sums a person's declared home values, subtracts 1.2 billion won for one-home owners (900 million otherwise), and multiplies the rest by a 60% fair-market ratio to set the tax base. Rates run 0.5-2.7%, up to 5% for three-plus homes — worked by declared-value case.