I've done a lot of plumbing fixture repair/replacement in my time, but chose to pay a local plumber that has experience in these old homes as I wouldn't want to do more harm than good as a DIYer on this.

If you feel you are harms way when there another correction then you should sell.

But no harm in checking out the other options. 

Rents (if applicable) will be current and be prorated as of the date title transfers.DEFECTS: Seller warrants Property to be free from hazardous substances and from violation of any zoning, environmental, building, health or other governmental codes or ordinances.

If the seller doesn't get that - no harm done - the buyer still gets the message that you want to buy.

The normal assumption is that the person who owns the wall has the duty to maintain it, if not maintaining it would harm the property of another.

When you post negative comments you're doing more harm than good.I apologize for suggesting the OP listen to the Podcast.

Seems he was thinking it was some kind of a goo type substance, like maybe food/grease.

There is no harm done in expanding your mind.

I would split it or prorate it and tell her that you are a good guy for doing it and not keeping the whole amount. that she caused you harm by you taking her by her word.