I don't yet know about the health of the seller but this could be an interesting exercise even if I don't purchase.

Congratulations on the upcoming baby and hopes to great health.

Much like a business doesn't need to allow everyone into their establishment, however the moment you try to explain why, you'll be opening yourself to a whole bunch of possible human rights complaints.

If they're on disability and don't have a job or a large volunteer commitment and they're not obviously physically disabled, get a full confidentiality release of their mental health history so you can determine if you can cope with having them as a tenant. 

Just had an IRS audit with someone who took that approach - they got crushed.Remember the human element of the law - it is not just what is on the books. 

If she is unable to have a civilized conversation then maybe you need to put some showing notes in your listings to the Agents to just beware of the neighbor who suffers from some kind of mental health issue <-- not too sure if you are allowed to do this since technically I believe this is a protected class but I would maybe consult with your local real estate board.

Human nature doesn't change, so sellers will be just as lazy and/or busy 20 years from now and would rather hire you to deal with selling their house than do it themselves.

As a complete aside, here's a few other snippets about me: my cat, Bucket, is an 8 yr old Cornish Rex and thinks he's a human toddlerI've been married to my AMAZING husband for 4 yearsI enjoy reading & knittingI try to work out a few times a week (but my husband is the major athlete in the family with marathons, triathlons, etc.)I SOO appreciate Bigger Pockets and all of you members! 

Investing goes beyond just numbers, there's a human element to it.

They are getting to the point where they need around the clock care and need to sell their house  where they lived to help pay for the health care and living expenses .