geomago

let grouped = cars.reduce( 
    (groups, curr) => {
	    let key = curr.make + ',' + curr.colour;
		if (groups[key]===undefined) {
			groups[key] = {count:1, minPrice:curr.price, maxPrice: curr.price };
		} else {
			groups[key].count++;
			groups[key].minPrice = Math.min(groups[key].minPrice, curr.price);
			groups[key].maxPrice = Math.max(groups[key].maxPrice, curr.price);	   	     
		}

geomago

let grouped = cars.reduce( 
    (groups, curr) => {
	     let key = curr.make;
         if (groups[key]===undefined) {
		     groups[key] = {count:1, minPrice:curr.price, maxPrice: curr.price };
   	     } else {
	   	     groups[key].count++;
	   	     groups[key].minPrice = Math.min(groups[key].minPrice, curr.price);
	   	     groups[key].maxPrice = Math.max(groups[key].maxPrice, curr.price);	   	     
   	     }

geomago

let unique = cars.filter ( (item,index) => index === cars.findIndex ( car => car.make === item.make && car.model === item.model) );

// RESULT IS:
[
 {id:1,make:"Ferrari",model:"812GTS",price:336000,colour:"rosso corsa"},
 {id:2,make:"Ferrari",model:"F8 Spider",price:262000,colour:"giallo modena"},
 {id:3,make:"Lamborghini",model:"Aventador S",price:329400,colour:"blu le mans"},
 {id:4,make:"Bugatti",model:"Chiron Pur Sport",price:3000000,colour:"blue"},
 {id:5,make:"McLaren",model:"New GT",price:203000,colour:"helios orange"}
]

geomago

let carsAsString = cars.map( (item) => JSON.stringify(item));
let unique = [...new Set(carsAsString)].map( (item) => JSON.parse(item) );

// RESULT IS:
[
 {id:1,make:"Ferrari",model:"812GTS",price:336000,colour:"rosso corsa"},
 {id:2,make:"Ferrari",model:"F8 Spider",price:262000,colour:"giallo modena"},
 {id:3,make:"Lamborghini",model:"Aventador S",price:329400,colour:"blu le mans"},
 {id:4,make:"Bugatti",model:"Chiron Pur Sport",price:3000000,colour:"blue"},
 {id:5,make:"McLaren",model:"New GT",price:203000,colour:"helios orange"},

geomago

cars.sort( (a,b) => a.make < b.make ? -1 
                  : a.make > b.make ? 1
                  : a.price > b.price ? -1
                  : a.price < b.price ? 1
                  : 0 );

// cars is now:
[
 {id:4,make:"Bugatti",model:"Chiron Pur Sport","price":3000000,colour:"blue"},
 {id:8,make:"Bugatti",model:"Chiron Pur Sport","price":3000000,colour:"red"},

geomago

let maxPrice = cars.reduce( (prevPrice, current) => prevPrice < current.price ? current.price : prevPrice, 0);
let priceyCars = cars.filter( (car) => car.price==maxPrice );

// RESULT IS:
[{
    id: 4,
    make: "Bugatti",
    model: "Chiron Pur Sport",
    price: 3000000,
    colour: "blue"

geomago

let maxPrice = cars.reduce( (prevPrice, current) => prevPrice < current.price ? current.price : prevPrice, 0);

geomago

let maxPrice = cars.reduce( (prevPrice, current) => prevPrice < current.price ? current.price : prevPrice, 0);

geomago

let maxPrice = Math.max(...cars.map(item => item.price));

// RESULT IS: 3000000

geomago

let car = cars.reduce( (prev, current) => prev.price<current.price ? current:prev, {price:0});