"Everyone wants a proprietary deal, until they get one." - Fatigued independent sponsor who's dealing with a slow-moving seller.
Proprietary deals are popular because they're exclusive and ideally priced below FMV.
However:
• A seller who has retained a banker signals that they're motivated & ready to sell.
• Bankers are excellent process managers: equipping the buyer with what you need for underwriting (w/ data room) and moving the deal through stage-gates (= momemtum).
• Bankers can serve as a bad cop, especially since they have built a trusting relationship with the seller.
• Bankers reduce the risk of seller's remorse (seller changing their mind or withdrawing).
• If you do one deal with a banker, they will send you more deal flow in the future.