I usually show up for a "surprise" visit before I leave Indy. I take a walk through all of the areas to make sure the dogs are being treated properly and the staff is compitent. I will usually catch a staff member doing something he/she wouldn't in front of humans, but its not a deal breaker (using foul language casually/ talking to the dogs) something small.
Then I will talk to the staff to determine how they group the dogs. I explain Indy and his doggie preferences and see what they say usually they say he can play with anyone who he is nice to and is nice to him.
Also I like to know that they have ATLEAST one human per doggy area. Alot of places will have the yard sectioned off so that little dogs can play without fear of being bowled over by big dogs, etc. So I want one person per area at least to be watching. I like to see those people playing with the dogs too but I know that people get tired.
Then once I have satisfyed my curiosity, I tell them I am leaving Indy there for four hours. One hour in I call and ask how he is doing and then again at three hours. When I get there I expect a report. All but one place has been cool with giving me those reports. I look for the staff's ability to remember Indy's name and what he looks like.
When he comes out I pay close attention to make sure he is not stressed or upset. Usually he is happy and tired. I go out to the car, check him for cleanliness, scratches, bites, etc. He is usually a bit dirty but not covered in poo or anything just dusty or maybe a little bit muddy. I have encountered little cuts and scrapes but only what you would expect to find from dogs playing, no real wounds.
If everything is ok then I keep going. If not I don't bring him back. Its a lot of procedure but so far it has worked out.
I also don't like them to put him in a kennel during the day. The place I go to has an indoor place and out door place so Indy can choose where to go. They have beds for the dogs to lay down and plenty of water. They will feed him if I ask.