Well, if prior to your father's death, they held the property jointly, then your mother's tax basis would have been equal to 1/2 of what they paid for the property, plus 1/2 of any improvements up until your father's death, plus 1/2 of the fair market value at his date of death.
Obviously, you may have to due some estimating to arrive at the figures.
Once you arrive at that figure, you would take 1/3 of that number & you'll have your initial tax basis; to that you would add 1/3 of any major improvements that you & your siblings paid for over the years, if any.
You would also add your share of any selling expenses to this figure, including any legal expenses to force the division of the property; that would be your tax cost for determining the gain on the sale of your interest
in the property to your brother; the selling price would be the gross sales
price, not the net proceeds as you would add the selling expenses to the initial tax cost as I previously described.
Depending upon what tax bracket you find yourself in, not including the capital gain, your federal
capital gains tax could be anywhere from -0- to 15%.
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