What's the liability landscape look like when, for example, grandparents have their grandchildren under 6 visit and sleep over in a non-deleaded apartment? Or what about cases where a tenant doesn't tell the landlord they have children under 6 staying for extended periods, or even living there? The laws seem to require you to delead if children under 6 live there, but is there a legal definition of what "live" means?
You avoid liability by asking tenants to sign an agreement that they accept the presence of lead paint. Typically up until 180 days is temporary housing, beyond that is permanent.
I would make sure that there is no pealing paint in the apartment and include in your lease that the tenant is responsible for the safety of their visitors and must supervising all visitors under the age of 18.
I've consulted with several agents and REI and it's my understanding that simply "signing an agreement accepting the presence of lead paint" doesn't dismiss you from liability as a landlord/ owner. The law in Massachusetts is clear, for better or worse: http://massrealestatelawblog.com/2013/03/16/boston-area-landlord-hit-with-75000-penalty-over-lead-paint-violations/
@Peter J. As a landlord or owner occupied buyer, you are required to remediate lead paint for any dwelling where a child 6 years old or less will reside. It's not optional.
This is a good start:
It literally takes a child ingesting a chip of lead paint the size of a quarter to cause actual brain damage. This is not to be ignored or glossed over.
Whatever else you do in your REI career, please take this very seriously. The mental damage you can cause to innocent kids isn't worth saving money on your rental units.