Choose by what has changed.
Use the leak and damp spot guide for water appearing outside a fixture, a wet cabinet, or a patch of moisture. It focuses on location and timing, not a hidden source.
Use the slow and blocked drain guide for a change in how water leaves a sink, shower or other fixture. It helps you distinguish slow emptying, water that stays, and water returning, without choosing a clearing method.
Use the faucet and toilet guide for a drip from a faucet outlet, repeated filling sounds, or a change in ordinary fixture behavior. It helps you describe the operation rather than guess a replacement part.
More than one observation?
A sink can empty slowly and have a wet cabinet beneath it. A toilet can make a repeated filling sound and also have a separate drainage concern. Use the relevant guide for each observation and mention both when you call. You do not need to decide whether they are connected.
Use what you have already seen during normal use. Do not recreate a problem, dismantle fittings or reach into an unsafe area to complete a description.
A job question rather than a symptom?
You can call about a plumbing inquiry without using a guide. Describe the work you want to discuss and your property address. Ask whether that job and location can be accommodated, what access is needed, and what a visit or assessment would involve.
For planned changes, explain the intended result before buying a fixture. For a rental or shared building, clarify who can authorize work. Discuss any assessment charge and how proposed work and costs would be explained before you agree.
Contact details & questions for arranging work