Catalyzes the dephosphorylation of diacylglycerol diphosphate (DGPP) to phosphatidate (PA) and the subsequent dephosphorylation of PA to diacylglycerol (DAG). Also has undecaprenyl pyrophosphate phosphatase activity, required for the biosynthesis of the lipid carrier undecaprenyl phosphate. Can also use lysophosphatidic acid (LPA) and phosphatidylglycerophosphate as substrates. The pattern of activities varies according to subcellular location, PGP phosphatase activity is higher in the cytoplasmic membrane, whereas PA and LPA phosphatase activities are higher in the outer membrane. Activity is independent of a divalent cation ion and insensitive to inhibition by N-ethylmaleimide. 1,2-diacyl-sn-glycero-3-phospho-(1'-sn-glycero-3'-phosphate) + H2O = 1,2-diacyl-sn-glycero-3-phospho-(1'-sn-glycerol) + phosphate a 1,2-diacyl-sn-glycerol 3-diphosphate + H2O = a 1,2-diacyl-sn-glycero-3-phosphate + H(+) + phosphate a 1,2-diacyl-sn-glycero-3-phosphate + H2O = a 1,2-diacyl-sn-glycerol + phosphate di-trans,octa-cis-undecaprenyl diphosphate + H2O = di-trans,octa-cis-undecaprenyl phosphate + H(+) + phosphate Inhibited by Mn(2+) ions. Inhibited by phosphatidylethanolamine (PE) (PubMed:27405756). Optimum pH is 6.5 for DGPP phosphatase activity and 6.5-7.5 for undecaprenyl pyrophosphate phosphatase activity. Phospholipid metabolism; phosphatidylglycerol biosynthesis; phosphatidylglycerol from CDP-diacylglycerol: step 2/2. The N-terminus is blocked. Reported mass includes mass of a C-terminal His6 tag. The enzyme active site contains a catalytic triad that establishes a charge relay system. This catalytic triad is essential for the dephosphorylation of LPA, PA, and sphingosine-1-phosphate, but is not essential in its entirety for the dephosphorylation of PGP, the nucleophilic histidine alone is sufficient to hydrolyze PGP. Belongs to the PA-phosphatase related phosphoesterase family.