8(a), SDVOSB, WOSB, and HUBZone certifications each unlock different set-aside pools and sole-source thresholds. 8(a) has the highest sole-source ceiling at $4.5M (goods/services). SDVOSB follows at $4M. When stacked with a GSA Schedule, certifications enable agencies to issue sole-source task orders without any competition — the fastest path to federal revenue.