If you do it right you will not have to worry about 1099. Also if you use say redfin who already gives a rebate to buyers then you can get their rebate plus the 20 percent couldn’t you?
Again in some cases if your agent does things the right way you will not be subject to 1099.
Finally I am only attempting to help you maximize a rebate and reduce any tax liability. The quality of the representation is not related to a rebate. They are independent.