You typically need to justify it as something like an "in law suite"; no using the term investment. 

If they didn't disclose this roof leak you may be able to win a lawsuit against them for the non disclosure but being practical it's small potatoes and not worth the risk, cost and time.

A lot of times a lawsuit is filed when the statute of limitations is approaching. 

Try to hide it/fail to disclose it and you risk a future lawsuit.

. :)  How does having a property manager shield you from lawsuits (if at all)?

If you have an attorney involved means your in a lawsuit LOL>

I'm curious if anyone has a real life example of how Umbrella insurance saved them from a lawsuit?

He files a lawsuit. 

Will depend on several factors like the type of property, type of tenants, your risk tolerance, other assets you own, your estate planning, laws where the property is located, etc.Any lawsuits would be limited to the assets of the LLC and not your personal assets (assuming you run the LLC appropriately and the corporate veil is not pierced).

The mobile home was paid off years ago, but at the time of the sale there was an old lien still on the title from a previous mortgage company that went out of business so part of the contract stated that there would be 120+ days allowed to provide a clear title to the buyer.Within weeks of closing the deal my parents started receiving complaints and threats of a lawsuit from this lady's daughter because she said the home was in worse shape than they thought.