Whether it’s hauling your paddling craft from a paved parking lot across the sand to a beach launch or transporting your boat and gear along a portage, a cart can make carrying your boat much less of an ordeal regardless of the terrain. There are several key factors to consider when selecting a cart.
The choices of carts are many, and selection based mostly on the type of boat (weight, width, etc.) and the types of terrain over which you'll be carting your canoe or kayak. Consider, too, the load limits it can bear; many are less than 100 pounds while top load weights can be upwards of 200 pounds. Other factors include the actual weight of the cart and how easy it can be broken down and stowed.
Wheels are the most critical element in a cart's make-up - too narrow and they may sink into the sand; too soft and wide, they may be sluggish on harder ground. A wider, softer tire travels more easily over soft terrain, with less impact/resistance than from a narrow wheel.
Wheels/tires are typically pneumatic (air) or solid/foam cored (airless). Air-filled tires (included the "balloon" type) can be adjusted for hardness of terrain, but can also leak and/or be hard to re-inflate in the field. Airless tires are not adjustable: what-you-have-is-what-you-get. However, depending upon the width, it's always ready to perform. All wheels/tires should be firmly secured/locked onto the axel/frame, yet easily removed for stowage if the cart folds down or is disassembled.
Most frames are sturdy, lightweight, anodized aluminum; a few are also made of molded polypropylene. Typically frames are: 1) center-cart carry; 2) end-cart carry or; 3) plug-in (typically incorporating scupper holes on SUPs). Carts either collapse/fold down into sectional pieces for stowing, or disassemble quickly and easily. (take care not to lose any separate pieces such as cotter pins for the wheels).
As an alternative, whitewater and smaller rec’ boats can be carried on your back with a harness system that typically includes broad, weight-bearing straps, padding at critical support points and adjustable for a more personalize fit.