I am having my dog stay at a sitters home for 8 days, is there a list of emergency or general rules between sitter and owner i.e., dog gets sick, not working out, gets in dog fight with another dog there etc.?
Always discuss every concern during the meet and greet, if you are not satisfied with the answers you get from the sitter, move on to the next. If your dog has particular issues or special needs, look for a more experienced sitter, perhaps one who is also a trainer.
A good sitter will have a readiness plan for cases where things are not working out, I have put together a network of Rover sitters I work with, that I have met , have seen how they are with the dogs so I have back up if needed. This way I can suggest the sitter who I think would be a better match for the dog. Having said that, I find that even dogs that seem they might not be happy in my home at first, usually settle right in within the first 24h so I wouldnt worry so much about it.
Rover also has a program where they have sitters ready to take in dogs that have not done well with another sitter. They usually are more experienced sitters with the set up and skills necessary to take dogs without a meet and greet, dogs who might have behavioral or anxiety issues, that sort of thing. So in a situation where you would be out of town and your dog would need a new sitter mid-stay, you can contact Rover and they will gladly help you find another, better suited sitter for your dog.
Like Deb suggested, a trial stay can be very helpful. With first time clients who's first booking is for more than a couple days, especially if the clients will be out of town, I recommend a daycare day trial booking prior to the long booking. That way the dog can get used to me, to being in my home, I can better asses if the dog will "work out". It just makes everyone more at ease, the dog included.
I'd advise the owner & sitter have a conversation before the stay regarding any owner requests and sitter commitments as to how these potential situations will be handled. Another consideration that may alleviate some concerns is to first book a single overnight stay - before the 8 night stay.
Deb and Fannie offer great advise. Make sure to do a Meet and Greet and take a list of questions and concerns with you to ask the sitter. I also recommend doing a trial overnight. Rover Support is available 24/7 to assist both owners and sitters in any emergency situation that may happen to come up, for any reason. And as Fannie said, rover has a list of experienced sitters ready to take a dog. If you know your dog doesn't do well with other dogs, look for a sitter that takes only 1 dog or dogs from 1 family at a time.