Cowboy builders can ruin a house extension or renovation project, making a large project with a large budget even more expensive. Of course, finding a reliable builder is key to your home project running smoothly and to achieving a result that reflects what you wanted and that will last. However (and as we all know too well) not all builders are equally conscientious and professional. If you spot any of the following signs, you may have bagged yourself a cowboy builder – a hazard to your home and your budget.