Flat-Fee MLS vs. FSBO vs. Redfin for a Rehab

I have a property in need of rehab (multi-unit that could also be a single family) I'm going to try to sell and minimize seller's commissions (at least see if I can do it this way). I've read numerous forum discussions on, say, FSBO, or on Redfin, but does anyone have any pros/cons or a preferable way to sell? Do the basic flat-fee MLS companies do any better or worse than FSBO or Redfin?