I am in no way affiliated with any of these services. These are just some resources I've come across in my research. Good luck FSBOs!
USRealty.com - (Updated) $19 for 10 pics, $99 for premium listing (30 pics)
xflatfeemls.net - As little as $89 for 1mo, or $109 for 3mo. +$30 for 30 pics. Tons of options like Centralized Showing Service, Open House announcements, lock box
100dollarmls.com aka AltRealty - I believe this is the lead generation tool for Frankly
unitedbrokers.us - $95 min, $295 30 pics
homediscovery.org - $199 min, $359 for 30 pics
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You can essentially "DIY" buy a house and save the 2.5-3% commission in either a home price reduction or a cash rebate. But the simplest, most convenient way is to work with an agent that will rebate you anything over 1% commission. Usually there's about a $2,500 min though but in this area that's generally not a problem.