A buyer broker agreement is a contract with the buyer and the broker to work together for a specified time period to help the buyer find a property.
Posthumous [ a. - Born after the death of the father, or taken from the dead body of the mother; as, a posthumous son or daughter. - Published after the death of the author; as, posthumous works; a posthumous edition. - Being or continuing after one's death; as, a posthumous reputation. Meaning of 'posthumous' (Princeton's WordNet)
In law, a legacy is something acquired by inheritance, or by a Will (law). In historical terms, a legacy is something that is handed down from one period of time to another period of time. A historical legacy can be counted in later times as a good thing or a bad thing.