What is the year of the home?
The price you quoted equates to over $100.00 per lineal foot…that is price gouging… at least around here… I understand that the cost of living in CA is over inflated yet $15,000 to repair 1200 sf residence, I suspect my subcontractors would come over for half that price to do the job. My exterior siding subcontractor has been driving as far as Maine to do jobs that are over priced and I have been sending my roofing crews several hundred miles to keep them busy but I digress.
Rambuilders has documented and video how and why patch jobs and improper installation is not acceptable, they have an excellent website which is full of detailed information as to the various types of stucco systems and the pros and cons of each.
I know we have limited information as provided by David but it just doesnt make sense keep putting a bandaid on problem… again, I know that we have only a limited amount of info that has been provided; yet the fact remains that moisture being trapped (looks like 48" high) in a system that was not designed for such.
It is evident that the construction industry throughout the US has lost vital details from which things were done in Europe and other parts of the world…yet the principles are still the same…with exteriors it is essential that we properly manage moisture and water away from the building envelope.
My wife and her family are from Europe and they are appalled at some of the building practices that go on here. There is a reason that they have buildings over a thousand years old and yet here in America it is rare that we inspect homes over 100 years old.