dennism, you might want to order your eliquid with a double, triple or quadruple shot of flavor, if your favorite vendor does this. (Mt. Baker Vapor and a bunch of other do).
Thus, if you order 12 mg./ml. with a quadruple shot of flavor, you could then cut it with your PG/VG mixture to get a 4:1 deal for mere pennies with no flavor dilution.