How to keep my pizza hot and crispy during transport
Pizza parlors have adapted to using thermal bags to slide the pizza boxes into and keep the pizza relatively warm. One or two of these might be worth the investment. 18" square x 5" would be for larger pies, but you can get smaller bags, the 5" depth would hold two standard pizza boxes stacked on top of each other. There are a lot of similar products on the market which may work, but I linked a restaurant quality bag. Your local restaurant supply store may have them in stock (and most sell to the public).  The bags eliminate the worry about humidity, although many restaurants use a thick sheet of something similar to wax paper to prevent grease from bleeding through to the box.