To qualify for the 121 exclusion you have to sell your main home at a gain. Selling lots does not count.

If building was attached to land, maybe:

(3) Vacant land -

(i) In general. The sale or exchange of vacant land is not a sale or exchange of the taxpayer's principal residence unless -

(A) The vacant land is adjacent to land containing the dwelling unit of the taxpayer's principal residence;

(B) The taxpayer owned and used the vacant land as part of the taxpayer's principal residence;

(C) The taxpayer sells or exchanges the dwelling unit in a sale or exchange that meets the requirements of section 121 within 2 years before or 2 years after the date of the sale or exchange of the vacant land; and

(D) The requirements of section 121 have otherwise been met with respect to the vacant land.