将流畅的界面与构建器模式一起使用

我试图通过在下面创建人员构建器对象来理解流利的构建器模式。我已经编写了想要使用的代码，但是在实现它时遇到了问题。我的问题如下：

1. 调用时HavingJob()，这将创建一个新作业，然后可以仅使用该作业的适用方法对其进行配置，并最终将其添加到此Jobs人的集合中。感觉应该返回它，以便可以在其上调用其他流畅的工作方法。不确定如何暂时实现该功能以允许在该级别及更高级别进行链接。
2. 实施IJobBuilder方法时，我无权访问它们在HavingJob()方法中创建的特定作业，因为我需要返回，IJobBuilder以将流利的方法限制为仅与作业相关的方法。HavingJob()使那些特定的作业方法可以在仍允许链接的同时对特定作业进行操作的诀窍是什么？
3. 一旦走到以结尾的流畅路径IJobBuilder，我将无法再打电话Build()或HavingJob()添加其他工作。答案是拥有一个IJobBuilder继承自的单独实现PersonBuilder吗？

    public class Person
    {
        public string Name { get; set; }
        public List<Job> Jobs { get; set; }
        public List<Phone> Phones { get; set; }
    }

    public class Phone
    {
        public string Number { get; set; }
        public string Usage { get; set; }
    }

    public class Job
    {
        public string CompanyName { get; set; }
        public int Salary { get; set; }
    }

    class Program
    {
        static void Main(string[] args)
        {
            var p = PersonBuilder
                .Create()
                    .WithName("My Name")
                    .HavingPhone("222-222-2222")
                        .WithUsage("CELL")
                    .HavingJob()
                        .WithCompanyName("First Company")
                        .WithSalary(100)
                    .HavingJob()
                        .WithCompanyName("Second Company")
                        .WithSalary(200)
                .Build();

            Console.WriteLine(JsonConvert.SerializeObject(p));
        }
    }

    public class PersonBuilder : IJobBuilder
    {
        protected Person Person;
        public PersonBuilder() { Person = new Person(); }
        public static PersonBuilder Create() => new PersonBuilder();
        public PersonBuilder WithName(string name)
        {
            Person.Name = name;
            return this;
        }

        public PersonBuilder HavingPhone(string phoneNumber)
        {
            // Need instance of phone
            return this;
        }

        public PersonBuilder WithUsage(string phoneUsage)
        {
            // Need instance of phone
            return this;
        }

        public IJobBuilder HavingJob()
        {
            // Need to create a job here and return it so that IJobBuilder methods work on specific instance right?
            return this;
        }

        public Person Build() => Person;

        public IJobBuilder WithCompanyName(string companyName)
        {
            // How do I set the company name if I don't have the job instance here
            job.CompanyName = companyName;
            return this;
        }

        public IJobBuilder WithSalary(int amount)
        {
            // How do I set the salary if I don't have a specific job instance here
            job.Salary = amount;
            return this;
        }
    }

    public interface IJobBuilder
    {
        IJobBuilder WithCompanyName(string companyName);
        IJobBuilder WithSalary(int salary);
    }