A busy roofer might not consider this worth his time and effort to look at and perform what is probably an easy fix. A handyman who has experience with roofing and other types of exterior repairs should be able to help you.

First take a good look at it. Is there ice with water ponded behind it? Is the gutter or facia loose? Are there shingles missing?

Most roofing problems are obvious but you have to get up there and look at it.

Number one---no one---and I mean NO ONE---can diagnose a water leak over the phone or the Internet. The only way is to see---and physically test(if necessary) the problem area.

The least expensive solution of which I can think is to hire a reliable experienced handyman to diagnose the problem.

Otherwise, find a reliable roofer who will come out and look. The problem there is determining a reliable roofer----there are a LOT more fly by nighters than experienced diagnosticians. It is not difficult to slap opn shingles---I taught total no cluers how to do that for Habitat for Humanity volunteers in less than an hour on a weekly basis.