Checkboxes with multiple attachments

I need to make a clients legal documents list.
In each client card a sales person need to upload to library client’s Charter, Questionary, Registrar confirmation, Certificete of goodstanding ets (10 different types of documents, some of them need to be updated). I want to organize this form like a checkbox with attachments otherwise it will be a mess.
I see that attachment field is only one and see no way how to make multiple attachments. Please help me with it.
This type of collecting documents is very usual and time consuming activity for office staff.

Dear @1116,

I would recommend to use List/Library control instead:

You can add as many List/Library controls on your form as you need.