Almost every argument about plumbing work is an argument about something nobody agreed at the start. Not the price, which is usually discussed. It is the things around the price: who puts the tiles back, whether the tap was in the quote, and what happens if the same leak comes back in a month.
This is the single most useful thing you can do, and it costs nothing. A plumber quoting on “there is a leak” is guessing. A plumber quoting on “there is water on the bathroom floor near the wall, it started three weeks ago, it is worse after somebody showers, and the wall feels damp” already has a shortlist.
- How long it has been happening. A leak of three weeks is a different job from one of three hours.
- Whether it is constant or tied to something: after a shower, when the motor runs, only in the morning.
- Whether anything has been done to it before, and by whom.
- Whether the wall, floor or ceiling nearby is damp or stained.
The same question as with any trade, and worth asking for the same reason. Somebody came out and spent time; charging for that is fair. Not knowing whether it is being charged twice is not.
This is the one that causes the most trouble, and it is one sentence to settle. Concealed pipework means breaking tiles or plaster. Ask, before work starts, whether they will make it good afterwards, whether that is in the price, and whether they will match the tile.
A plumber who says plainly “I break it, you get a tiler” is being honest and you can plan for it. What you cannot plan for is finding out afterwards.
A quote for “fitting a mixer” may or may not include the mixer. On a bathroom refit the fittings can be most of the cost, so a quote that is silent about them is not really a quote. Ask for the brand by name rather than by grade. “A good one” is not a specification, and the difference between two mixers that both look chrome is the difference between five years and fifteen.
Ask specifically whether the guarantee covers the LABOUR or only the part. A tap that leaks again in a month is rarely a faulty tap; it is usually how it was fitted, and a parts-only guarantee covers none of that. Most careful shops will stand behind their own work for a period and say so readily.
Before agreeing to any more work, ask what they think is causing it. A recurring leak that has been “fixed” twice is a symptom of something upstream (pressure, a corroded line, a joint that keeps moving), and a third repair to the same spot is very likely a third bill for the same fault. A plumber who has a theory and can explain it is worth more than one who simply agrees to come again.