My OH made a sparrow multi nesting box last year and we argued where he should put it. I wanted it somewhere where I could see it on a regular basis and he wanted to put it in the paddock.
He stood it on a low wall that retains the garden from the house while we argued it out. I then noticed that great tits started to take in some nest building materials so we have had to leave the box where it is. The female has been sitting for quite a few days and we expect them to hatch any time. It is very vulnerable to cats and dogs but there is not much we can do about that now except stop our own dog from going near it.
Here is a picture of the box and the great tit about to go inside.
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