Yep, that's what it is: A lawsuit.The biggest challenge with a quiet title suit is property noticing of the respondent, the other party (or the estate) who allegedly owns the parcel in question. 

At death, the mortgage balance was $0 but then the mortgage company attempted to foreclose alleging that they paid the deceased almost $500k.  

Just last week the tenant got arrested in front of the house (allegedly on narcotic & gun possession) & now my client really wants them out. 

It's allegedly been remediated, but I honestly don't think they did much.

I'm calling the police to inform them today.http://www.bostonglobe.com/metro/regionals/north/2013/07/27/contractor-alleged-scams-detailed-police-reports/75mMu9gE6P78imFjzMJrLM/story.htmlkeywords - boston, massachusetts, new hampshire

I have heard of informing the lender preventing calling claim several times on BP, but I have yet to see the legal dots connected.Estoppel, in very broad terms, is a legal principle that bars a party from denying or alleging a certain fact owing to that party's previous conduct, allegation, or denial.

I spoke to the asset manager and he said the deal was kind of a mess, the person doesn't exactly have the money (it is allegedly in some kind of trust account?)

I would only add that you should keep the returned application for your records, and add notes on how/when you notified the applicants of their approval, but heard nothing back as of X date, and approved next potential tenant on X or Y date.I guess sate laws on statutes of limitation for civil suits (like alleged discrimination, charging fee but not running credit reports, or running credit reports with no application, etc) vary.

If I show up on the date of the scheduled move-out inspection (with or without movers), can I be sued by the tenant who allegedly intends to stay beyond his lease? 

In the 18th century, such an allegation would trigger a challenge (white gloves flapping) and a duel to defend my name and achieve satisfaction.