A system for finishing surfaces with a finishing material includes a handle assembly with proximal and distal ends. A material reservoir is mounted on the handle distal and includes an inlet and an outlet. A material applicator tool is mounted on the reservoir and receives material from the reservoir outlet. A discharge mechanism includes an extendable-retractable component or linear actuator connected to the reservoir for discharging or reloading material. An alternative embodiment includes a lockable, compressible gas spring. Another alternative embodiment includes a rotating element driven by a reversible motor mounted on the handle assembly. The rotating element drives a discharge mechanism in a discharge direction of rotation, and reloads the reservoir in a reload direction of rotation. Multiple alternative embodiments of linear actuators are disclosed. An alternative embodiment includes a push-to-open valve mechanism.