give her your address. I don't see that she is asking for any information from you like a credit card number.
As for yahoo...you would be surprised at what is associated with your yahoo account now. If you have ever read an article on Yahoo news that you saw on Facebook, your facebook account is now tied to yahoo.And the list goes on.
If all you give her is your business location, worst case is you might end up with a Toyota that (in our state,anyway) you can keep until she pays the bill.
It's probably a scam, though. You will just have to follow it through until you get to the point where it becomes certain. My guess is she will pay with a fake check or money order that is WAY higher than your estimate and ask you to wire her the overcharge amount.