Where the water appears matters as much as the sound of the drip.
The short answer
Dry the visible surfaces, then observe whether water leaves the spout, gathers around a handle, appears at the faucet base, or comes from a supply connection below. Stop if observation requires disassembly or creates an overflow. Note whether hot, cold, or either handle changes the symptom.
What to notice
Four different leak paths
A spout drip continues into the basin after the controls are closed. A handle leak appears during operation or around the stem. Water at the base can come from the faucet body or splash. Moisture below can involve supplies, shutoffs, sink connections, or water traveling from above. Name the path rather than calling everything a washer.
Keep usage clues
Record whether the drip is constant, appears only while water runs, or follows movement of the spout. Note stiffness, looseness, noise, and changes in flow. If a single-handle faucet has a brand or model label, photograph it. Do not rely on appearance alone to order an internal cartridge.
Define the finish of the repair
Ask whether the proposal addresses the identified source, a corroded connection, or a complete faucet replacement. Confirm who supplies the fixture and what happens if existing shutoffs do not close. Protecting the counter, reconnecting accessories, testing hot and cold, and removing packaging should be clear in the scope.
One useful question
Can a dripping faucet be diagnosed from a photo?
A photo can show the location and fixture style, but not every internal condition or intermittent path. A provider may need to operate, dry, inspect, or measure components. Ask what the photo establishes and what remains uncertain before purchasing parts.