Record the rain pattern at the rear.
Say whether water runs over the gutter edge, gathers near an outlet or drips from a connection. Leaves, twigs and fallen moss pieces can form part of collected debris. Gutter clearance does not treat the roof for moss. If the rear gutter is hidden, describe the visible water pattern without claiming a blockage you cannot see.
Previous clearance or building alterations can help explain the request. A displaced gutter or leaking join may need a different assessment from accumulated leaves. Do not adjust fittings or attempt to reach behind an obstruction yourself.