When we built our barn last year, one of the foundation walls developed 2 hairline cracks and both were leaking water, enough to cause large puddles on the floor. They came out and patched the cracks but they were still leaking. The leaking stopped as soon as the ground thawed. Our builder is installing gutters, in a few weeks, along the back which will divert the water away from the foundation. He says if it leaks again next Spring he will dig a trench along the foundation and seal it from the outside.

I know a long story, but my builder took full responsibility for our water problem and seems to be keeping on top of it. Your builder telling you to find an expert is ridiculous. If you have not paid in full, I would not pay anything more until all the leaks are fixed.

I would also suggest looking at your grading around the foundation of the entire house. One simple fix is to regrade and make sure the ground, around the entire foundation including under decks or porches, slopes away from the house. And all downspouts have long enough extensions to keep the water away from the foundation.

Good luck.

I suspect my last house had a high water problem. My sump pump ran very often, even on dry days. I was naive at the time, thinking this was normal.

I agree with msafirstein. I would try delaying closing on the house if possible. Sounds like the builder is trying to pass his problem on to you.
I feel this "expert" should be at the builders expense, and also costs to remedy the situation.

-jasper