The tenants are elderly and I have a feeling they were unable or unaware of what had happened and the issue was not addressed in a timely manner.

@Devin Elder there are also some free CRM (I believe that is Customer Relations Managment) tools available.

or perhaps someone who was elderly, a vet or who was disabled? 

Also, don't rule out similar types of services - elderly or assisted living, housing for deaf or blind, some sort of physical rehabilitation, etc. 

Typically, they target the elderly or what I would consider a vulnerable group to part with their equity (not always). 

The other side is rented to an elderly woman, my banker's in law.

tenants who often are "renting" from multiple owners (often preying on the elderly whose properties tend to be more neglected and violations left uncorrected) and consequently subleasing out the property they rent to others, without owning the property nor paying rent on it, generating multiple streams of property.one dude i found to be doing this, while showing a few apts and having him apply to rent a 2nd at one of the properties i manage, when he had just put a deposit already on a 1st, when confronted, even boasted it's his and his 'homies' method of 'investing in the new economy'!

Thats conveniently left out of the analysis.I'm always suspicious of "investors" targeting the elderly population for any kind of strategy.

Hi Fellow BP members,There is this property for sale (4000sqft on a 0.6acre lot) that the owner (an elderly woman) inherited free and clear.

She was elderly and unable to talk on the phone.