We're not "responsible" for "confusion" or "injuries" or "dead pets" caused by our "signs."
As a general rule of thumb, if you aren't sure how to use a punctuation mark or indeed why it exists in the first place, then please "stop" using it. This is especially true when you are operating a flea market, a place where people are already suspicious that the "things" they are paying for may not exactly be "actually the things they are paying for." For instance, it's already pretty creepy to, say, buy an antique clown mask. Now imagine a vender telling you to "buy" an antique clown mask, or to buy an "antique" clown mask, or worse, to buy an antique clown "mask." That mask has a curse and you are going to die. Now do you "see" why punctuation is important?