Thanks.
not sure if a flat is a good idea. She might call AAA to fix it.

An odd idea came to me.
If you plugged in one of those memory savers into the odb port, what happens if the battery is disconnected and someone tries to unlock the car with a remote, or tries to start it?
I think it might be better if it looked dead from the outside and can say she must have forgotten we didn't fix it yet, instead of opening and cranking but not starting.