Be careful about offering a 无中介价格. Once you've signed the seller's contract with the agent, they can always go after you for commission even though you try to sell the house by yourself, and COLDWELL BANKER is not a small firm, so they likely will have a group of lawyers sitting in the office just to deal with this issue and ensure their firm will get all the commission they are entitled to get from the recent land transactions.
Even after your contract with them has expired, They still have a period of time to claim for your commission if you happen to sell the house a few months after the expiration of the seller's contract.
I'd suggest you to carefully read the seller's agent agreement you signed. Check and make sure starting on what date you will be freed from agent commission, and only offer the 无中介价格 at that time.