It would appear from the stories told so far that three of the four died from knife wounds or blunt-force trauma....but they won’t say which of the four was the odd person on this deal. No one has reported any gunshots heard or bullet wounds with the family...meaning whoever is into this....used strictly a knife. The burned Porsche was found roughly 15 miles away on a major street area of Annapolis Road (Prince George’s County). Generally ‘PG’ is a thug-infested area with a fair amount of drug sales.
My humble guess is that there’s some guy who had some cash flow requirement in a hurry. He picked some rich family and assumed that the husband had some safe in the house with something of value. Things went wrong, and the results are obvious. He used the Porsche as a cash-for-trade item but his connection read through the issues and knew that cops would be all over this vehicle and whoever it was connected with. So burning it on the street was the only way to cover up your tracks.
I think it was more professional than someone who selected this family randomly. They seem to have been a well chosen target, the perpetrator (s) even took the time to know the house keeping schedule, they held the family hostage for quite some time (most 'normal' thugs would do a hit and run, not wait as if they were timing the expiry of an automatic time lock), they killed the people and took the time to burn the house (most 'normal' thugs would just shoot or knife/bludgeon them), and as for the porsche found in the 'hood' that doesn't mean anything in and of itself. If I was to ever go rogue, I would also probably leave the burnt out car/murder weapon/murderous leprechaun in an area known for drugs and crime.
Without knowing much about this case, that family was the victim of a professional robbery (probably held hostage while the robbery happened offsite) and then followed by a murder. Probably mob related. Why? Because they were professional enough to pull it off, but STUPID enough not to realize that video of them driving off in the porsche would immediately cast doubt on a murder-suicide story. That mix of brilliance and stupidity is usually indicative of the mob.