was your sister was on the title, because she would have to sign off on the sale?
I assume you kept all the proceeds, reported 100% of the sale on your return and took all the depreciation. this creates some legal and tax issues.
again if she was on the title, consult a lawyer because I believe
she was entitled to half the proceeds and should have reported 50% of the sale on her return and you should have reported only 50%. you were only entitled to depreciation on 50% of the basis. what happens if your sister can legally come after you for 50% of the proceeds and does? further there's a question of whether a partnership return should have been filed for each year your sister and you owned it. there can be substantial penalties to fail to file the return if required.
