Lease commercial store

[N.A. N.A.]

I have a friend who has a commercial building with about I think it's either 3 or 4 stores in it. He said one of the units is going to be vacant soon. The unit that is going to be vacant is in a very popular location and his unit already has a ton of agents and people asking the business owner about the space. The question I have is this. Is there a way he can advertise or handle the lease with an open contract to any broker wanting to bring in their client? He was with a broker before and he thinks his broker was trying to get a double popper by bringing in his own client. Other agents might have also held out their clients because they knew the lease commission had to be split. He wants to advertise it so that it's open to any agent that has a customer to make sure he gets a lot of lease offers on the space and gets the highest amount possible. He knows he won't have problems leasing the space but doesn't want to corner himself with one broker and a contract with him. He didn't have a great experience with the previous 2-3 commercial agents for his other unit. He knows his space is very very popular and there are a ton o f people and agents looking at the space because they know it's going to be vacant soon. Any advice on what to do and where to advertise it if he wants to leave it open to many brokers? Would love to hear your thoughts on this. Thanks!