Chance contrives that this gentleman shall have in his possession a large sum of money which he shows to Ronald, who is greatly in need of money.

Opportunity suggests the murder, provides the weapon, and gives Ronald the next room to his intended victim in a wing of the inn occupied by nobody else.
"Your theory as to how the murder was actually committed strikes me as possible enough--up to a certain point.

You think that Ronald, after waiting until everybody in the inn is likely to be asleep, steals out of his own room to the room of his victim.

He finds the door locked.
Chance, however, has thoughtfully provided him with a window opening on to a hillside, which enables him to climb out of his own window and into the window of the next room.

He gets in, murders Mr.Glenthorpe, secures his money, and, finding the key of his bedroom under the pillow, carries the body of his victim downstairs, and outside, casting it into a deep hole some distance from the house, in the hope of preventing or retarding discovery of the crime.