It really depends on the chef and city you are living in. In Santiago, Chile service prices start at 10,000 pesos ( ~20 USD ) per guest. If the size of your party is larger the price can be lower however that is generally the starting price. One chef in Santiago ( Chef Nancy Bavestrello [1] ) delivers meal packages at a lower price if the order volume is higher.
[1] https://chefsurfing.com/en/chefs/chile/region-metropolitana-...