On a house built in the 1950s, the shingles are often not the first thing to fail. The weak spots are the joints: the flashing around the chimney, the valleys where two slopes meet, and the rubber boots around plumbing vents. We check those first.
Some of these roofs have been patched many times, with tar over tar around the chimney. Tar buys a season or two. When we find it, we tell you whether the flashing under it can be fixed or has to be replaced.
In a two-family house, a leak on the second floor can show up in the first floor ceiling. With your tenant's okay, we look in both units, so the repair goes where the water gets in.
So we do not guess at a leak from the driveway. We trace the water to where it gets in, and you see the photos before we fix anything.