This work aims at providing a guide for the calculation of investment and operation costs of a process to treat diluted streams of heavy metal ions. This process is composed of two stages: (1) a metal concentration stage by polymer supported ultrafiltration; (2) a polymer regeneration and metal recovery by electrodeposition. First of all, the most relevant parameters to be used in the process design will be correlated with the key working variables. Next, these parameters will be related with the cost of the main investment of the plant, providing Williams equations based on both literature and suppliers’ budgets. Finally, a detailed costs calculation for the most representative values of the working variables will be presented as example.