@Carolyn Fuller I heard Cozy was great but unfortunately when I started renting out my homes it was not available anymore so have only been using apartments.com and it has been working great for me. Maybe since I never used Cozy I don't know what I'm missing. I love the fact that they will place a sign on the front yard with the apartments.com logo. To me this gives it a better look and makes it feel more legitimate than having a generic rent sign.
Zillow is great to find tenants and well worth the $10 a week to list. I was able to get so many inquiries in the first 3 days. I also get a good amount of inquiries from apartments.com. I prefer the tenant screening on apartments.com so I just tell everyone to do it there. I tried Zillow application/screening but find it is not as comprehensive as apartments.com.
I loved the leasing agreement on apartments.com. it's a wizard format where it asks you questions and then generates the agreement and sends it to all parties. Everyone e signs it and your done. On Zillow you have to upload it. I also find their payments feature very helpful.
Please let me know if I'm missing something that would make another service better.