Build a specification first
Sanitaryware, taps, waterproofing, tiling, ventilation, waste connections and making good. Write down the make, model and quantity of each item; a general allowance can hide a very different finish.
Keep supply and installation separate
A supply quote can exclude measuring, fitting, removal and the trades needed to reconnect services. Check whether the fitter is quoting a total job price or time plus materials. Enter the whole team’s daily cost if using this model.
Changing the layout
Moving services and repairing hidden defects can add work that a like-for-like replacement avoids. Ask for these items to be priced separately. The contingency is a reserve, not a promised maximum cost.
Common questions
Does this include appliances or tiling?
Only if you include them in fixtures and materials. Use the written specification to avoid omissions.
Sources & methodology
This page uses original budgeting guidance and transparent arithmetic. Example prices are chosen illustrations, not a survey of UK market prices. Replace them with written quotations.
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