The commission is between the seller and his agent. Usually the agency contract is exclusive and the agent is entitled to their commission if sold within the period set forth in the listing agreement. Most listing agreements are between 3-6 months in length. You may want to employ your own agent to submit your offer as their commission is paid by the seller and not you. I always strongly recommend that you DO NOT USE THE SAME AGENT and you have your own agent represent you. THERE IS A CONFLICT OF INTEREST WHENEVER THE AGENT REPRESENTS BOTH THE BUYER AND SELLER. These are known as a DUAL AGENCY representation and the California Dept of Real Estate allows such representation but I would never recommend using a dual agent. Some states disallows such dual agency representations and California should ban such practices because the seller's agent is supposed to get the highest price for the seller and the buyer's agent job is to get the lowest price for his client. Now how can an agent that represents both parties do both??? Real estate agents love dual agency because they don't have to share their commission with the buyer's agent.