I've been told that the problem we have with the crack in the wall where it looks as if the kitchen part is "falling away" from the rest of the house can be fixed by "underpinning".
Is this true? Is it worth doing it cost wise and who on earth do I ask to look at it for me? Is it a specialized job or can any builder do it?
We are in Durban, South Africa.
Repairing a foundation would depend on the specific circumstances. You should get more than one quote with specific details as to what they propose to do to repair things. Like the old saying goes... "You get what you pay for." or... "There's more than one way to skin a cat..." The best price might not be your best option if the repairs aren't going to be done right.
Have a look at this... http://en.wikipedia.org/wiki/Underpinning
It'll give you an idea of what may be involved to do your repairs.