i think almost all of the platform in crypto space is built with peer-to-peer method because they believe that it will speed-up the transactions while using smart-contract and blockchain technology to remove the trust issues between both parties.
Not all property owners have time to find buyers that is why they are hiring brokers to manage their properties so I think Cestates is not removing the brokers from the picture. in addition, they offer much larger commission compare to the traditional ways that they can get in real-time.
this question has been discussed on their telegram channel regarding the broker side, cestates is encouraging them to join the ecosystem because they will benefit from it using the platform. they can sell property much faster because cestates will open the market globally.
if i remember correctly they are conducting a series of group discussion wherein they invite every people who are into real estate especially the brokers so they can introduce the platform and showcase the benefits they will get if they join the cestates ecosystem.