Wow, either we never hear from xhonzi or he posts nonsense 12 times and then writes a song about it.

I assume your comment about calling the cops was in regard to Home Alone and not Skyfall. iirc Kevin witnessed one of the robbers actually dressed as a policeman during the film. I haven't seen it in a while.

In skyfall, Bond went to a place he knew well. The house had a stocked gun room but all the guns were sold off to a collector upon news of his apparent death. So, to be fair he was expecting the house to be better stocked when he arrived.

I do agree that M should never have been in the house once Silva's men arrived.