Can I keep my rental as an open listing?

I'm a first time landlord and I'm thinking of keeping my rental as an open listing instead of being exclusive to a real estate agency. The agent is pressuring to be exclusive since they will post on MLS for me. But by doing so, if I find someone who wants to rent my place like a relative or friend, they would need to pay a real estate agency fee. I'm thinking of making them add into the contract that if I find a tenant outside of their efforts the tenant does not need to pay the agency fee. Can someone explain the pros and cons?