Wanting to haul small loads of dirt or stone, debris,etc.  Which would be handier, a small dump truck or a dump trailer?

I see the advantages of a dump trailer as lower maintenance costs, can haul equipment inside it and it can be parked on a job while still having a truck to use.

The dump truck would be a self-contained unit and would eliminate potential access issues in tight areas by not having 2 pieces of iron to maneuver.

Thoughts?