Buyer Fee, Assigned by My Agent on The Offer Contract

[Brad Rafalski]

I've bought more than 8 properties in my life. While working with a new realtor, he inserted a $500 fee, paid by me (the buyer) in an offer I was making on a duplex. The fee was said to cover his fees owed to his agency. I've never heard of this before, he removed it upon my questioning, but isn't this what his 3% of the sale is supposed to cover?