Commission from Sale to Tenants in Prop Manager Agreement?

[Paul Cordasco]

I have settled on a property manager for my recently acquired rental property. In the agreement they sent over there is a clause that stipulates that they receive a 4% commission if I was to sell the property to tenants they place. Is this typical? Can I negotiate this? Is this just an assurance I use them as my broker in that case? Any experienced POVs here are welcome. Thanks BP community.