Assignemnt #102 and Keychains for sale 2

Code
/// Name: Yordan Rashkov
/// Period: 7
/// Program Name: Keychains for sale 2
/// File Name: KFS2.java
/// Date Finished: 3/29/2016

import java.util.Scanner;

    public class KFS2
    {
        public static void main(String[] args)
        {
            Scanner k = new Scanner(System.in);
            
            int pricePerKey = 10;
            int opt;
            int numOfKeys = 0;
            
    
            System.out.println("Ye Olde Keychain Shoppe");
    
            do
            {
                System.out.println();
                System.out.println("1. Add Keychains to Order");
                System.out.println("2. Remove Keychains from Order");
                System.out.println("3. View Current Order");
                System.out.println("4. Checkout");
                System.out.println();
                System.out.print("Please enter your choice: ");
                opt = k.nextInt();
    
                System.out.println();
    
                if (opt == 1)
                {
                    numOfKeys = addKeychains( numberOfKeys );
                    System.out.println("You now have " + numOfKeys + " keychains.");
                }
                else if (opt == 2)
                {
                    numOfKeys = removeKeychains( numberOfKeys );
                    System.out.println("You now have " + numOfKeys + " keychains.");
                }
                else if (opt == 3)
                    viewOrder( numOfKeys, pricePerKey );
                else if (opt == 4)
                    checkout( numOfKeys, pricePerKey );
            } while (opt != 4);
        }
    
        public static int addKeychains(int numOfKeys)
        {
            Scanner k = new Scanner(System.in);
            int keyNumberNow;
            
            System.out.print("You have " + numOfKeys + " keychains. How many to add? ");
            int add = k.nextInt();
            
            keyNumberNow = numOfKeys + add;
            
            return keyNumberNow;
        }
    
        public static int removeKeychains(int numOfKeys)
        {
            Scanner k = new Scanner(System.in);
            int keyNumberNow;
            
            System.out.print("You have " + numOfKeys + " keychains. How many to remove? ");
            int remove = k.nextInt();
            
            keyNumberNow = numOfKeys - remove;
            
            return keyNumberNow;
        }
    
        public static void viewOrder( int numOfKeys, int pricePerKey )
        {
            int totalCost;
            
            System.out.println("You have " + numOfKeys + " keychains.");
            System.out.println("Keychains cost $" + pricePerKey + " each.");
            
            totalCost = numOfKeys * pricePerKey;
            System.out.println("Total cost is $" + totalCost + ".");
        }
    
        public static void checkout( int numOfKeys, int pricePerKey )
        {
            Scanner k = new Scanner(System.in);
            int totalCost;
            
            System.out.println("CHECKOUT");
            System.out.println();
            
            System.out.print("What is your name? ");
            String name = k.next();
            
            System.out.println("You have " + numOfKeys + " keychains.");
            System.out.println("Keychains cost $" + pricePerKey + " each.");
            
            totalCost = numOfKeys * pricePerKey;
            System.out.println("Total cost is $" + totalCost + ".");
            System.out.println("Thanks for your order, " + name + "!");
        }
    
    }