There is one thing which strongly points to an inside job. According to what I have read, the medical reports say that there was a time gap of half an hour between the 2 murders. Any lay man will agree that if this murder was done by outsiders, they would do it within a span of couple of minutes, and not waste time there. So the killers were well protected in the confines of the house, which gave them all the sweet time they needed to commit the crime.Without insider involvement or support, this time gap would have been impossible. Also hiding of Hemraj's body only, indicates a planned motive to shift the blame of Arushi's murder on to Hemraj. But then all this hiding and shifting of bodies needs time...and how could they get it...unless people inside were party to the whole crime...!!??