see a lawyer. there are complications. one, they do not own the land. second, the land appears to have been sold but not the residence. if the land is to qualify the residence portion must be sold within 2 years of the land sale but then they don't own either parcel so it probably doesn't matter. third, the land must be adjacent to the residence. adjacent means a common side. this land is across the street so it's probably not adjacent.
also some of the taxes on the gain are your responsibility
When the property is sold before the life tenant dies, then there is no "step-up" in basis and capital gains are paid based on the original purchase price of the property with adjustments for improvements, etc. that haven't been deducted. The resulting capital gain is divided up between the life tenant and the remainderman based on age and life expectancy.
