Key phrase from @KrisD15 : "If the amount is included in your 1099"
In other words, you can deduct a real estate commission rebate as a business expense only if you paid income tax on the full amount of the commission (including the rebated amount).
You do not issue a 1099 for the rebated amount, because the rebate is not considered taxable income to the buyer. It is considered a reduction in the selling price.
**Answers are correct to the best of my ability but do not constitute tax or legal advice.
