What do you want the big discount or a realtor who can do the job?

David,

Somewhere there is a disconnect, you maybe need to explain it to them in a different way.  If nothing else maybe be blunt and ask them why it is they keep calling.  There's a reason there and until you know it you can only make assumptions.

David, they want the discount and the advantage of having your knowledge.  2009 is the Year of Opportunity and by helping buyers who will not commit to an agent of your qualifications is the wrong way to start the year.  Cut them off or tell them you'll give their relative a referral fee (small) and complete the transaction for them.  If they cannot or will not accept those terms, you need to ask them politely stop calling you as you are an ehtical Realtor who just doesn't practice real estate behind another Realtor's back.

The relative must be the owner agent or something along those lines.  Explain your position to represent the Buyers interest in the purchase only.  There is something untold here.

I'm back, question:  Did you show them the house?  They told you they did not have a Realtor?  If nothing, get a referral fee from the relative Realtor on the flip side as you did the showing.

For now on, please ask them if they have a family friend, relative or enemy that they would consider using instead of you, or if they are working with one of the above.

Best of everything.

Have "Come to Jesus" talk and speak to the "relative" and the "buyers" set up a meeting to decide on who is who. Honesty goes along way. Agree on some form of referral fee and everyone wins.

They found out what all buyers find out when they believe that they can save money by finding the house themselves.

Finding the house is the easy part.

David~ I love Lenn Harley's statement above,  Finding the house is the easy part!  You just need to get to the bottom of what it is they need you for.  I hope the answer isn't free advice.....

Just explain that it would be unethical for you to interfere with the agency relationship of another agent, and you must withdraw from any further conversation with them.  I'm assuming you didn't have a buyer's agent contract going into this?  If you did, then you need to seek your broker's support in enforcing it, and inform the relative's broker that he/she is interfering with your fiduciary relationship with a client.

NEVER EVER SHOW A HOME in the future without a written agreement from the buyer to pay you your fee!

My suggestion is to tell them you cannot help them or advise them in any way and they should speak to "their Realtor."

All interesting comments.  I believe everyone should be honest with each other.  There is nothing like working very hard for someone and then to have them work with someone else.  If they are going to use their relative then that agent should be the one helping them.  There is nothing like doing someone else's work.  Just my opinion.  Keep up the great work David.