Where is the best place to find good multifamily investment properties?

[Grant T.]

I know that the term "good deals" is different for every investor but I am curious where people in the past have found the multifamily properties they bought? People in the past have told me "If it is listed on LoopNet or Redfin it is not a good deal". I used to believe them but after countless hours  over the months analyzing properties I believe I have come across multiple cash flowing properties with great room to add value and increase rent. For those to own or sell multifamily, do you believe that places like LoopNet and Redfin aren't good places to look for investment properties? Where have you found some of the properties you own or found for people? Are off market deals really the only way to go? Any and all advice would be greatly appreciated.