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)
The 'residue' of an estate is everything that is left in your estate after all debts, bills and taxes have been paid and all specific and non-specific gifts have been distributed. Leaving the residue of an estate to a named beneficiary is called a 'residuary gift'.