If you drop something in your home then go outside then go back inside and place that item somewhere and then go outside again the item should stay in the location you put it. I've noticed that this only works 80% of the time for me. I have 5 Dibella statues in my bedroom and one of them keeps falling.
I have constant problems with my Dibella statues too. It seems like I have to place them out of the way, where my housecarl/spouse won't knock them over, AND I have to place them somewhere where no other item spawned. Otherwise they fall over, or end up somewhere across the room. Or, like at Proudspire, somehow travel from my bedroom to the first floor entryway.
Besides that issue, I have had good luck with drop, leave, enter, & place method. I was able to line the shelves of Honeyside with mead bottles this way, and they're all still in place.