You will have to take the "bill of sale" to a local real estate attorney to review and to determine if it created an enforceable contract.
I am not a LA attorney, laws vary from state to state, therefore you should always consult a local attorney.
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I agree with the other answer that you need an attorney to review the bill of sale. Normally any transaction dealing with land must be in writing. If it was notarized but not witnessed, it may qualify as an act under private signature. If it has two witnesses, it would be an authentic act and should be filed in the conveyance records of the parish where the property is located.
Every situation is different and you should consult your own attorney to go over all the particular facts in your case. The answer given is only intended to provide general guidance regarding rights and responsibilities.
The bill of sale which is notarized is an authentic act, as required by Louisiana law to validly transfer ownership of property. If you have paid for the land, and you have a notarized bill of sale, your brother cannot take the acre of land back. You should file the bill of sale with the registry of your local parish court so that it is effective against other parties as well.
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