Waste of time to go pure FSBO by yourself and list on Zillow. You're just asking to get hounded by agents with nothing to do and time on their hands.
The agents with real buyers will avoid you. Fact of life. Do an agent assisted FSBO if you're really intent on saving $$. Like some of these other comments have mentioned, go with a company like Hauseit if you're in NYC for example that'll get you on the relevant broker databases and websites. For us it'd be RLS and StreetEasy etc. Good luck.