RichJ,
The comment regarding being wary of re-pointing almost certainly relates to settlement rather than damp. If a property is suffering settlement, it will show in fault lines which open up along the mortar joints and, occasionally, in fractured brickwork. If you just re-point the open joints and replace fractured bricks, it highlights the problem, so the 'solution' is to repoint the whole wall and try to disguise the area affected. Have a look at the inside as well - are there any signs of distress (cracks, creases in wallpaper) or have they decorated internally as well? It may be that there has been a problem which they have fixed and subsequently repointed/redecorated as part of the repair (in which case, they should tell you), but it may be that they have something to hide!
Edit: I've just re-read your last post and you do say that the interior has been freshly decorated too. Exterior repointing + interior decoration on a property which will require renovation work anyway spells settlement problems to me. Ask the vendor point blank. If he says there has been a problem which has been fixed (underpinning) ask to see evidence of the work done and any guarantees etc.