To the question about cleaning up TM blood, the buckets on backhoes are a lot larger than you realize unless you are right next to one. One good scoop, two at the most, and every bit of blood and matter can be moved elsewhere or perhaps buried 12 and a half feet as the first layer on top of the boys.
The farm is quite a ways outside of Philadelphia, way in the suburbs, almost considered a rural area. There is no comparing it to the crime level in Philadelphia proper. They could be two different countries, they are so different.
People leave keys in cars all of the time. People also leave keys under doormats, and on top of the casing around the door. The only crime in this area is the infrequent larger stuff, usually pulled off by a really dumb criminal who was caught right away. This isn't the kind of area that has muggings or beatings or any of the other lower-level crime that you will see in a city street. I never felt unsafe wandering around that area alone even as a teenager, and I still don't if I am up there alone. This kind of thing is very isolated.
To all of the questions about why didn't the drug chain above CD come out and how much money was there and all of those kinds of things... We probably only know the tip of the iceberg of what came out in questioning. Of course, they are going to withhold any information that would get in the way of an investigation of any other crime.
The FBI was on the scene extremely quickly. Many reputable sources have said that the FBI doesn't get involved that fast, unless whatever is going on intersects with an already active investigation. Think of how many multiple killings happen. If you aren't aware, it's a lot. I work peripherally to the legal field, and cases where multiple people are shot during drug deals come across my desk often. I just served on a mock jury about a real multiple homicide during a drug trade for law school students to practice trying a case a couple months ago. The FBI doesn't fly right up to any of those.
