By all means establish rules!
Check out this topic for ideas on rules. http://www.etiquettehell.com/smf/index.php?topic=127002.0
What seems perfectly obvious to you may not be to them.
Also do some due diligence on why the mom won't give her the address. It is an issue with the mom or the child?
When do you expect her to move out? What do you expect her to be doing to move out? (e.g., Work/find work to save up $1000 for deposit or save up $100 per week or finish the semester or whatever.)
Also you could say that staying with you is contingent upon her continuing schooling.
How would you feel if you see her buying a bunch of DVDs instead of saving? Perhaps you might ask her to create a budget.
If you do chores in lieu of rent, then write down the chores and say when you expect them to be done. By Wednesday night, the following tasks are to be completed: X, Y, Z
Agree on what will happen if she does not do the chores/clean up after her pet.
Like other say, come up with a list of "topics" and then talk with her about them.
So decide ahead of time what is okay with you. For deal breakers, mention them ahead of time.
"No overnight guests, no smoking, no drugs, no new pets. If that is not good for you, then you staying here won't work out."
For more optional things, you could say
"I like to watch TV in the living room. I will make a list of shows/times I watch. At other times feel free to use the TV."
"If you have people over, I would expect them to leave by X:00. If you need to study as a group later than that, then the library might be best."
"i go shopping on tuesdays, so let me know if you want to go with me."