This is subjective and depends a lot on your location but, in my experience, I believe Zillow has some of the best prospects.
I’m not sure why, but I think it has a lot to do with how serious someone is when they are searching. Or “how far down the funnel” as marketers say.
The closer they are to pulling the trigger on a rental property, the better the applicants tend to be. That’s because the not-so-serious ones tend to get weeded out and discouraged.
It could also be because Zillow lets applicants re-use their applications and credit checks to apply to as many properties in 30 days as they want.
This tends to motivate renters. They fill out their application, get their credit reports and apply to their top property choices. It becomes “real” at that point.
Those that don’t fill out an application probably aren’t as motivated to find a rental or may not be as qualified and are hoping to work directly with a landlord who won’t screen as thoroughly as other property managers.
Don’t get me wrong, I got plenty of unqualified leads from Zillow but it wasn’t nearly as many as I got from other rental sites like Facebook Marketplace (more on this below).