Make like you're strong as an ox with a little help from the Makita Power-Assisted Flat Dolly. You can load up your cart heavier, and pull it farther thanks to this big boy's Makita-built BL Brushless Motor, and your choice of one or a pair of 18V LXT batteries. The motor has enough fire to carry up to 275 pounds of material, and a single 6-amp-hour battery will get you up to 60 minutes of haul time under load (about 1 mile). Add a second to double the run.
The Dolly has 2 speed settings, and can hit a maximum Power-Assist of 2.5 MPH on a 12-degree incline. It's also reversible, so you can push or pull it as a wheelbarrow / hand truck, and the removable rear wheels adjust from 19" to 30" to accommodate various work settings (L-shaped stabilizing legs are also included with the purchase). LED lights on the side of the dolly frame illuminate the surrounding area when your Makita is in action.