Why are you cancelling?
If you no longer want to sell, they can "withdraw your listing". Contract is in force, but home is not on the market.
If you want to use another broker, you'll need to explain why.
If you are unable to negotiate a release, you can postpone the sale until the listing expires by asking your Realtor to "withold" the listing.
IMHO it is best to be honest.
My colleagues are all giving you good advice. Most of the time the broker will allow you out of the listing contract. No one wants bad publicity or unhappy clients. However, the broker will want to know the reason as to why. If you don't believe that your Realtor is performing up to his/her side of the deal then you will want to let the broker know this. If you haven't talked to your Realtor about this, then definitely do so. A problem can't be fixed if they don't know there is one. Please feel free to ask any questions or contact me personally at firstname.lastname@example.org Thanks and Good luck!!
What has caused you to change your mind? If it is the level or quality of service that is being provided to you, you might want to approach the agent's broker about the issues. One of three things could happen:
1. your concerns may be ignored
2. the broker may get the action you are looking for
3. the broker may allow you out of the contract w/o penalty
NOTE: Almost 100% of time brokers will allow seller cancel based on executed listing agreement.
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