According to this Advice forum, it seems many sellers are complaining about lack of access and control over their listings. Since Zillow and Trulia are now the same company, the policy is you're supposed to edit your listing on Zillow first, then it will populate / sync to Trulia within 48 hours.
Another option is to Google and research "Flat Fee Broker". This method is an alternative to full service brokers. It allows owners to pay a small fee to a flat fee broker to have their home listed in the local MLS system. You will be required per MLS rules to pay a commision to the buyers broker IF the realtor brings a buyer who submits an offer. You still save about 3% by not listing with a full service broker. It leaves the owner in full control for marketing the home, negotiations, disclosures, contract, etc.