The foyer phonograph hides the red bottle - wear the glasses and click the needle so the glow reveals it.
Double-check the stained-glass window before mixing colors; if the order isn't red, green, blue the ghost sulks.
Pet the bulldog twice or it won't release the teacup; the head tilt is the confirmation animation.
Set the melon tea on the side table first, then add the stairway leaf or the flavor never shows up in dialogue.
Sketching the lover on the mirror works best if you inspect the portrait from top to bottom before using the paste.
Alternate solutions unlock the 'reckless courier' badge, but they spook the manor enough to dim future hints.
You can speed-run the delivery by leaving the glasses on; they highlight interactables even through cutscenes.
Watch for the blue sparkles on wall sconces - they point toward hidden achievements tied to the bad endings.
Completing all three good deeds rewards a tiny epilogue where Earl Grey finally opens the study door.