I mean, for all we know, the house could have been painted with lead-paint bought prior to 1978, or by paint obtained from other sources, like industrial paint or paint from across the border where there are no regulations. Out of these three, the first concerns me the most. I mean, paint can last very long when stored properly, so lead-containing paint stored in the garage since the 70s can still be used by the owner today or even years from now. Who's there to stop him? Also, paint used in industry which contains lead can be obtained by a home owner (I don't know how, but I'm sure it's happened before) and be used to remodel or paint a new home. What do you think?