How do realtor commissions work when wholesaling with a realtor?

[Mahmoud Y. Elhalawany]

Hey there everyone! My partner and I have just closed on our first deal!! We have learned a lot but are forever in need of more guidance. Recently we have begun to add a lot of realtors/brokers to our cash buyers list. My question is this: When we shoot out properties and a realtor ends up bringing a cash buyer how does the commission get paid out? does it come out of the purchase price/assignment? or is it tacked on-top of the contract? We will almost always have the end buyer pay closing costs (There are rare instances where we will agree to split closing costs as part of a negotiation). The way we do our disposition is through a highest and best auction/bidding war on the contract, so assuming the realtor brings the cash buyer should we factor their commission into our calculations? will their commission affect our bottom line and or what the seller is getting is what i am asking. I keep getting different answers and it is really really confusing me.   

Thanks so much for reading everyone!