The cool kids tend to use a cart called the rock-and-roller. You can get add-ons for it that create shelves and things.
I’ve used the same old fashioned hand truck from Harbor Freight for three decades, changing out the wheels as they wear out. It’s narrow and shorter than a Rock-n-Roller, but makes it easier to navigate narrow spaces. Porta-Brace wanted an insane amount of money for a tripod holder… I bought a $1.50 metal electrical outlet box at the Ace Hardware and bolted that to the bottom of my cart’s frame; the tripod legs rest in it like a cup, the top gets lashed to the handlebars with bungees. Works great.
I recommend a cart with the fattest air-filled tires you can manage, to make it easier to traverse bumps. Also, get one or both of the smaller, swiveling caster wheels on the cart to be equipped with a foot-operated friction brake. This makes loading and unloading much easier on non-level surfaces outdoors.