title: Sequelize - Use set, add, create methods in models with belongs To Many associations
body: <p>I'm new working with sequelize, and I don't know yet, how implements the methods that sequelize create when associate models with BelongsToMany associations. For example:</p>
  
  <p>I have two models Users and Properties, a user can have more than one property, for each reason I've create the middle model PropertiesByUser when I have userId, propertyId, status and others fields. </p>
  
  <p>I'm creating the users and properties separately, but when I want add a property to a user is when the process is complicated for me, because I don't know How create or use the model PropertiesByUser for create, add, set, properties for user, or add users to properties, someone can help me please?</p>
  
  <p>I've read in blogs, some ways to use this but, any solution works. :(</p>