Total number of selected objects (N_T) for the faint-end (m_r ≥ 18.5) regime by adopting different N × σ_NMAD combinations for T80S/S-PLUS and LS-DR10-CBPF galaxy cluster candidate members selection and imposing different m_r-limit values (20, 20.1, 20.2, 20.3, 20.4 and 20.5). The lower panel show a set of 5 different N × σ_NMAD combinations within the m_r range of 20-20.5. The leftmost column of each set corresponds to target selections adopting N × σ_NMAD = 4 for both T80S/S-PLUS and LS-DR10-CBPF, followed by the N × σ_NMAD combinations (from left to right): 3.5/3.0, 3.5/2.5, 3.0/2.5; and 3.0/2.0 for T80S/S-PLUS and LS-DR10-CBPF respectively. As a reference N_T number (N_T) of selected objects is included on top of each m_r-limited set considering N × σ_NMAD = 4 for both T80S/S-PLUS and CBPF surveys. The blue line highlights how N_T varies as a function of m_r, if m_r = 20.5 (N/N_T = 1) is considered N_T is reduced to 60% at m_r-limit = 20. Each bar is decomposed by their corresponding parent survey catalogue: T80S/S-PLUS (green), CBPF (yellow) and common objects selected by both surveys(grey). The upper panel shows how the different N × σ_NMAD adopted combinations for T80S/S-PLUS and LS-DR10-CBPF affect N_T at each m_r-limit bin, considering N × σ_NMAD = 4 as a reference (N/N_T = 1). At all m_r bins the number of objects is reduced for the different N × σ_NMAD combinations, dropping down to a ≲60% of the selected objects at N × σ_NMAD-combination: 3.0, 2.0 for T80S/S-PLUS and LS-DR10-CBPF, respectively. The final m_r-limit at = 20.4 and N × σ_NMAD-combination 3.5/T80S/S-PLUS and 3.0/ LS-DR10-CBPF adopted to compile the Low-z faint (S1505) and Low-z faint suplementary (S1506) catalogues is highlighted in red.