Hello,

I am having some trouble understanding how to go about creating a module that extends another.

Here is what I am trying to accomplish:

I want to create a module that will be a specific type of order. For example, I have a client that does repairing/refurbishing/repairing/unlocking electronic devices. Each of those requests requires different information from the customer (Dropp off date, Pick up date, IMEI...). I am thinking of creating a custom module for each of those services, each with their own required fields, so that they can be kept separate. I want these to be tied to an invoice, if that makes sense. I have the base of what I am going to be storing in the database for each but I would like some help as to how to make a separate module for these, not just extending the original Sale Order. Do I have to create a relationship (one to one) for one of these orders to an order in the invoice database? I'm just having a hard time wrapping my head around this.

I would really appreciate some help as to whether I am going in the right direction and any tips to help me out.

Thank you.