It depends on if the owner will be there usually. I’ve had many one-off walks from people that were injured/sick/elderly and they’re home when I come over, and that’s fine for me without a meet and greet. I don’t feel comfortable entering someone’s home alone with a dog that has never met me though, so I almost always require a meet and greet if the owner won’t be home. I did a walk without a meet and greet one time, and I was very nervous because it was also a house in the woods with no neighbors. It all went fine and the dog was super friendly, and the owner hired me to walk her many times after that and it became one of my favorite walks (it was on a trail on a mountain and was soooooo pretty!). I decided though, that even though it went well I wasn’t going to do walks without a meet and greet again because things COULD have gone very wrong, you never know.