There are many negotiations that can happen here! The Realtor could approach the Seller, as part of the negotiation.
Keep something in mind...your Realtor is going to receive both sides of the commission, and if the home is listed with your Realtor, and he/she is representing you as well, legally, in the state of Colorado, your Realtor may need to back away as YOUR REALTOR, and become a "Transaction Broker (TB)". There is no dual representation in Colorado...there is in some states, but not here!
Or there are also other scenarios that may be available to either you or the Seller. "TB essentially means, your Realtor must be impartial towards both parties. With a purchase as important as this one, you will now either take everything into your own hands, or hire an attorney.
Listing agents are usually very knowledgeable about their properties (listed), but they were originally the SELLER's representatives. They will disclose everything they know, and whatever the Seller has told them.