Capacity should match realistic contracted demand plus a buffer for seasonality. A plant that runs too small increases unit cost, while oversized capacity leads to idle equipment and unstable cashflow. Evaluate hourly throughput, number of grades per day, changeover time, and storage volume needed to cover delivery schedules. Automation level should fit your skills and QC discipline: basic manual plants can work but require experienced operators and tight SOPs. For consistent road spec supply, automatic ratio control, pH dosing, temperature control, and inline density or flow measurement reduce batch rejection risk and lower total cost.