Hi djsherly
Actually, yes, I'd be a bit concerned. The cracks run through the bricks, not just the mortar joints, and this implies quite a lot of pressure on the bricks to cause them to crack.
As this is affecting the outer corner of the wall, this definitely implies that the strip footing has failed.
Failure of strip footings can come about from a variety of causes, the most common being moisture in the foundations / drying out of the foundations, particularly in clay reactive soils, and the effects of tree roots.
What type of vegetation is there within 5 metres of this wall, including on the neighbour's side of the fence? If there are lilly pilly or similar moisture seeking shrubs or trees, their thirst can have dried out the clay base causing the strip footings to roll. Even a couple of millimetres can cause tremendous pressure on the brickwork.
I have seen a house where this occurred, causing the brick wall to roll away from the house to a full arm's thickness gap!
No cracks inside the house, but the strip footings were irreparably damaged.
Cracking which follows the mortar joints is mainly due to the articulation joints perhaps being a little too far apart. Cracking through the bricks themselves would certainly warrant further investigation.
The roof beams and rafters should also be checked, as this pressure can be transferred through the brickwork to the timber framing of the house.
No: 1 Son was going to buy a very attractive townhouse a couple of years ago, but after we really looked at it we realised that numerous places in the brick walls - including high up under the eaves - showed signs of the walls being under pressure. Apparently there had been a large liquid amber tree in the front of the land at one time. The tree was removed just before the townhouses were built. As the soil re-hydrated this caused pressure on the footings, which transferred the pressure to the brick walls, which literally buckled a couple of millimetres horizontally and vertically.
There had previously been remedial work performed and the strip footings had been pumped with aerated concrete, but after much consideration we figured there were lots pf houses out there without all these problems so we kept looking.
We figured that the property had had nearly 4,000 hits on the website and had been on the market nearly eighteen months. If Son had wanted to sell who else would want to buy a property with potentially more problems of this complexity?
Have an engineering report done but be aware that once damaged it is very hard to make things right again. Of course, if you have any plans to extend the house out from this corner then you can fix the footings at the same time but do check for old creek beds, areas of fill, swamp trees, etc before you make a decision to buy.
Cheers
Kristine