Reditron unprofessional service/no support

Bought a Dahua DVR from them which is suppose to support up to 6MP cameras. Once installed, it did not work. Took it back, technician suggested we downgraded cameras to 1080P resolution, then it would work. Obviously a silly solution (who would want to downgrade picture quality from 5MP to 1MP - and remember you paid for 5MP). Then suggested we get a more expensive DVR, but they cannot take back the unit as the packaging was opened... how do you install a unit without opening it? As I said, really silly service and NO service. And the cherry on the cake is the management is forever busy, never available for such simple thing as clients