Statute of limitations on non-permitted renovations.

[Marie Buckingham]

What is the statute of limitations on homes that had their first floor renovated from garage space to living space when the home was built in 1983? I purchased this home and later found out later that there were not a permit pulled for the lower level being finished. And now I want to sell it, and discovered the square footage listed with the county is half what it actually is.  Please provide insight if you kindly would.