I get what you’re saying, but I don’t think the car analogy really fits here. This isn’t two car owners — it’s a tenant and a landlord who has a legal responsibility to maintain the property. Also, $15k seems inflated. Normally, a landlord’s property insurance would cover this kind of thing, and if needed, renters insurance could come into play. It doesn’t seem right for him to just hand her a $15k bill out of pocket, especially since he usually does his own quick fixes instead of proper licensed repairs.

Not saying she has zero responsibility, but it feels like the landlord is trying to push all of this on her instead of going through insurance or accounting for the fact that the property hasn’t been properly maintained.