You don't list or claim property improvements until the tax year that property improvement is placed "in service". It does not matter when the property improvement was done either. So you your case, you will enter nothing on your 2019 tax return concerning your renovation, since it was not available for rent at all in 2019.
Even if you did finish a renovation in 2019, if it was not "available for rent" in 2019, you will not enter it anywhere on your 2019 tax return.
