At the foundation

One of the things that I dread during a home inspection is when an inspector suspects a foundation problem. In most cases, it is the end of the transaction. But that’s OK. It’s when the buyer still wants the house, that the fun begins! ...Sigh...

House 1. This one was a big, beautiful old thing with a foundation that was about two feet thick. It was made of rubble. It badly needed pointing. It had shifted again, and again, from the look of the multiple lines of re-pointing at the corners. The engineer was called. He said that the whole foundation had to be pointed by hand and could be damaged if done wrong.
Mason 1 said the pointing job would be some 5-figure amount, done by hand. Mason 2 would do it for something under $5000, but would power wash it first to get the majority of the loose stuff off (which was wrong, says the engineer.)
My buyers walked away. The sellers then had a <$5000 estimate to show to future buyer prospects.

House 2. This was a more modern home with a back foundation wall that sat at an 80 degree angle. There was an engineering report showing extensive work done to stabilize the foundation that year. It looked convincing. The town records showed two more engineering reports of past extensive work to “stabilize” this foundation. My buyers were no longer convinced that this solution had really solved it. They walked away. The listing agent is still mad at me.

House 3. In this one, the back wall was brick above ground level. It was badly damaged. It was hard to see how bad it was because there were walls inside and shelves outside (in an attached shed.) The engineer was called. He recommended rebuilding the back wall. Mason 1 quoted something like $10,000, plus engineering plans for $2-6,000. He said the job couldn’t be done without those plans; the town would never allow it. Mason 2 said $5000; it doesn’t need plans and it happens all the time. The town agreed with Mason 2. An agreement was reached between the buyer and the seller.

Engineers and builders: Who should I believe? How can a non-engineer determine if a repair is junk or if it is effective? Do towns and cities know enough to permit this work?