Ideally, employ a builder recommended by friends or family – or, if you are using an architect, a contractor they regularly work with. If not, ask for references from previous clients for similar jobs. Make sure they were happy with the builder’s work and conduct, and that he has the right skills and experience for your project.

— When researching a tradesman, try to find out if he has to go back to sites after completing jobs – often a sign of poor work.

— Get three written quotes. Be careful to compare like with like and don’t automatically take the lowest: he may not be able to finish the job for the money or may charge a lot for extras later.

— Ensure that you get an agreement in writing. This shouldinclude a description of the work that is to be done, the timescale,an itemised breakdown of costs, hours of work and payment terms.

— Be wary of a builder who won’t buy materials upfront, since it could be a sign he can’t get credit, adding to the risk he could go bust halfway through doing your ensuite bathroom.

— Don’t pay money in advance unless specialist items are needed or it’s a long project.

— You only need a project manager on very big jobs – we have done work for £1m without one.

— Ask to see a copy of the builder’s public liability insurance certificate.

Manuel Costa is a London-based builder whose family firm, MH Costa Construction, has been shortlisted for several awards; mhcostaconstruction.co.uk

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