Free puppy to good home

Rocko is an 8 month old puppy that is mixed with 3 or 4 breeds. He is a very good dog but I can't keep him because I already have 2 dogs in my apartment. He needs a yard because he loves to run and he's good with kids and other dogs. I got him from my son who was unable to take care of him. I was told he has his shots but they didn't have any paperwork so I'm not positive. He's free to someone who would love and take good care of him. He's potty trained and obeys really well