No. You're no longer regarded a For Sale By Owner once your property is listed on the MLS. But that shouldn't be a problem. Your listing agreement with the agent is usually "entry only," which means it just covers the MLS entry of the property listing and can be terminated at any time. Consider this a technological hurdle to overcome in order to obtain all of the agents' marketing prowess. No less than for a nominal fixed fee. You're not enslaved to a long-term exclusivity arrangement that you can't break.