Generally the brick wall strip footing should finish flush with the wall face. You can see the neighbour waterproof membrane turned up against the wall footing. This is where footing…

If you are both building true zero lot (houses built right to boundary) then it's very important that the footings and slabs of each house remain separate.
So if their…

It's just poorly dug footings on your neighbours builders behalf. It was probably dug with a machine rather than hand dug to a line so there is some extra width…

Yep, it looked to be a simple fix and it's a pretty standard mistake the first builder on a zero lot makes without realising it's going to affect anyone else.
We…