Which of the following is a precaution an estimator should take when using an allowance in an estimate?

When using an allowance in an estimate, keeping a proper record of expenditures is crucial. This precaution ensures that there is accountability and transparency regarding the funds allocated for various items or contingencies. By maintaining accurate records, an estimator can track how much of the allowance has been spent, compare this to the initial estimates, and make necessary adjustments or informed decisions in future estimates. Proper documentation helps in managing the project's budget effectively and aids in justifying any changes or overruns to stakeholders, which is essential for maintaining project control and integrity.

In contrast, adjusting estimates based on material trends, estimating without concern for item quantities, or listing materials based on preference do not prioritize the management of the allowances effectively. While staying informed about material trends is important for long-term planning, it does not directly relate to managing allowances in an ongoing project. Failing to consider item quantities can lead to inaccuracies in the estimate itself, and basing decisions on personal preferences rather than objective data undermines the estimator's responsibilities to provide a realistic and justifiable estimate.