Saw this trailer today, and loved it. I think it's a great example of how simple trailers can be--although it had film and actors, the sets were everyday, and there wasn't a single special effect. What really caught my attention was the twist at the end. Nobody points it out, but you can't miss it; the inherent conflict leaps out at you.
See what I mean? Gorgeous conflict. The book's Goodreads blurb never would have caught my interest, but this trailer did. And if you break down the elements, they are easily reproducible in cheap, simple terms--
1) Child actors could be a younger sibling, your own kids, children of your good friends or relatives.
2) The film could easily be replaced with still photos of a boy coloring, the mantelpiece, the swingset.
3) The setting--house, park, muddy road--are also found just about everywhere. Your house. A park or school playground near where you live. The muddy road is a bit more specific, but a stream, cornfield, etc would work as well.
4) Music -- this is the kind of generic song you could find online for free with little hassle. Not all music videos need dramatic soundtracks (or old fashioned songs.)
In other words? You could do this. I could do this.
Food for thought.
Truly and always,