Edit: I am going to consider deterring the dog with vinegar / other strong smells. I am waiting for Sydney to stop raining all the time as I don't want the smells to wash away. Thanks for your suggestions! I no longer feel vengeful and will be more proactive instead :)
I've thought about putting a big sign saying something like STOP SH*TTING ON OUR LAWN but I feel like this would make them do it more. Or maybe even make other people join in.
So I think I should install an outdoor security camera to catch them. Any recommendations please?
Also if you have an alternative solution, I'd like to hear it :)
Thanks!
See here for similar but not the same, it helped that they knew the dog in that one.