If you delead (and maintain the standard) you will be in the clear.Here's the law (emphasis added by me):460.100: Duty of Owner(s) of Residential Premises (B) Whenever any residential premises containing dangerous levels of lead in paint, plaster or other accessible structural material undergoes a change of ownership and as a result a child younger than six years old will become or will continue to be a resident therein, the new owner shall have 90 days after becoming the owner to obtain a Letter of Full Compliance or a Letter of Interim Control, except that if a child younger than six years old who is lead poisoned resides therein, the owner shall not be eligible for interim control, unless the Director grants a waiver pursuant to 105 CMR 460.100(A)(3).

Pet owners tend to pay more and stay longer.If you learn how to screen applications well, you'll have fewer problems.

We have so much data and so many ways to analyze properties but we'll regularly lose bids to investors with fewer resources. 

Otherwise, I would say there are lots of ways for the situation to go wrong with fewer upsides long term.

I'd imagine far fewer people know about FF compared to ABB as well. 

On the other hand, there are still some Very Dangerous areas.

Yes, a data center will create a lot fewer jobs and therefor demand for residents.

This is not as likely because there are typically fewer sales out there and it is not as reliable as the first method described. 

This was rapidly addressed, but some areas of Mexico really are quite dangerous and may not improve anytime soon.

Now, there are occasionally unicorns but in the past 12 months I've been looking I've seen fewer and fewer.