The test I do is the following:
1)Response to strangers:
a) have tester outside of room knock on the door, gauge dog's response.
b) Tester comes into room and attempts to greet the dog, speaking in a high pitched voice and sitting down. Gauge dog's response. Does it want anything to do with tester, or is it trying to get as far away as possible?
2)Check out sensitive areas:
Tester sits either on the floor or chair, depending on how large the dog is. While petting, tester gently pulls on ears and tail, squeezes feet, and neck ruff. How does dog respond to each of these?
3) sound sensitivity:
While dog is not paying attention, drop a metal bowl onto a non-carpeted floor. Gauge dog's reaction.
4) Play response:
tester tries to engage dog in play. How does the dog respond? If the dog does want to play, how does it play? does it mouth/bite?
5) Resource Guarding:
a) Food: place bowl of food on the ground and let begin to eat. Use a fake hand to attempt to pet the dog and reach for the bowl. How does the dog respond?
b)High value treat: Give the dog a high value treat such as a rawhide. use a fake hand to attempt to pet the dog, and take the treat away.
c) toys: if the dog is interested, engage a dog in play with a toy. How does the dog react when you try to take the toy away?
I do all of those before taking the dog into the rescue. After settling into a foster home, we will introduce them to other dogs to determine how they are with them. If anyone has any other tests, I would love to hear them and add them to my list