Repairing stone veneer or redoing it
If a few stones have popped loose and the wall behind them is dry and solid, resetting them is usually enough. If you see dark stains, soft spots or loose stone across a whole section, water has usually gotten behind it, and sticking the face back on just hides the cause. Then I'd take that section off, fix the barrier and the wall, and reset the stone. I'll show you which one your wall needs.
What drives the cost of stone veneer
The biggest pieces are the wall's size, the stone itself and the prep. Natural stone usually costs more than manufactured, and a wall that needs cleaning, lath or a scratch coat costs more than one that's ready. Lots of windows, outside corners and cut ends mean more cutting and fitting. Height matters too, since scaffolding takes time to set and move. On a historic house, the extra review can stretch the schedule more than the price.