Re: How big a holding tank vs. camping
There's a simpler cheaper way. Buy a box of plastic bags, buy a big box of clumping kitty litter. Throw about a half cup of kitty litter into a bag, add another half cup after use, if needed. The stuff is incredibly absorbent. When you're done, tie a knot in the bag. Stow the full bags in another bag, they're cheap enough.
Wagbags are what, about two bucks each? Twenty bucks should get you at least fifty 5-6 gallon size garbage bags and the huge box of kitty litter. The wagbags are clever, they supposedly are higher tech, yadayada, they're damned expensive.