The only must haves are a jar with an air tight lid, water, veg and non-iodized salt.
Edit: almost forgot - Nitrile gloves!!
However, with no air lock you must burp your jar every day.
To make life easier get some air locks and lids. The bubbler style are simple and far better than the caps and built in lid types in my experience.
A scale to weigh the salt etc.. is useful.
Hand blender or blender is nice.
Glass fermentation weights made for fermenting are useful, but you can use other items as weights.
Sieve, fine mesh strainer or chinois if you want smooth sauce.
Packer is handy. I often use a carrot.
Vinegar, whatever type you like.
Xantham gum if you want to thicken your sauce.