JSFiddle - React, Tailwind, and code Playground

JavaScript

var data = [{
    "name": "name1",
    "custitem_color": "3",
    "custitem_ribbon": "1",
    "baseprice": "10.00",
    "cost": "12.00"
}, {
    "name": "name2",
    "custitem_color": "4",
    "custitem_ribbon": "2",
    "baseprice": "20.00",
    "cost": "15.00"
}, {
    "name": "name3",
    "custitem_color": "6",
    "custitem_ribbon": "3",
    "baseprice": "30.00",
    "cost": "22.00"
}, {
    "name": "name4",
    "custitem_color": "8",
    "custitem_ribbon": "4",
    "baseprice": "40.00",
    "cost": "18.00"
}]

var output = {};
for (var i = 0; i < data.length; i++) {
    for (var item in data[i]) {
        output[item] ? output[item].push(data[i][item]) : output[item] = [data[i][item]];
    }
}
console.log(output);