Quantity take-offs (QTO) are detailed measurement of materials and labour needed to complete construction project. They are developed by an estimator during the pre-construction phase. This process includes breaking the project down into smaller and more manageable units that are easier to measure or estimate. The level of detail required for measurement may vary. Estimaon and costing is an essential part of building construction and accurately forecasting the cost of projects is a very important skill in demand today technology has changed the quantity takeoff method, and today advanced processes like BIM raised the technology bar with more complicated systems which has significantly increased estimation accuracy.