• In Odoo there is a contact called Final Consumer defined to  be used in simple invoices;
• When you change this contact data, the info that you put there is always gonna show in simple invoices;

• Invoices can be in three states Draft, Open or Payed. An invoice in the draft state can be deleted;
• Draft Invoice
• • Select Action > Delete;
• Open Invoice
• • Select Cancel (left upper corner);
  • Justify why you want do cancel it; 
• Payed Invoice
• • Create a credit note Modify option;
  • Create  Reimbursement;

• 1º Step: Select an invoice with different lines with VAT defined;
• 2º Step: In the lines, after the Taxes column, terá you'll have a new column called Exemption Reason onde where you can add the exemption that you want; 

• 1º Step: Access to the Billing > Customers/Suppliers> Invoices menu;
• 2º Step: Choose the invoice and, in the right upper corner, next to Total field, click the little blue "i" on the left > Reconcile;

• If you want a fixed discount you can opt:
• • Make a credit note with the value that you want to discount;
  • Register the discount at the payment level;
  • Convert the fixed discount in percentual discount and apply it in all the invoice lines;
    
    
• OPTION 1: 
• • Issue a credit note, adjust it's items unique value according to the discount you desire;
    
    
• OPTION 2:
• • After the invoiced is filled, select the Register Payment button;
  • In the Payment Amount field, define the value that the customer payed (with the applied discount);
  • In the Payment Difference field, select Check Invoice as Fully Payed;
  • In the Publish Difference in field, define the account 682 Discounts Granted;
  • Click in Validate;
    
    
• OPTION 3:
• • In  each line from the invoice, in the Discount field, apply the discount you want;

• It's not possible to revert the situation, however there are two solutions for the problem:
• • If it's in Draft deverá you have to cancel it and create a credit note from the invoice that you want to reconcile;
  • If the state is Open or Payed deverá you have to issue an invoice with the same value to cancel the credit note;

• If you register a payment and it appears the Odoo Server Error error, that's because the Payment Method is not correct;
• For a correct configurations do:
• • 1º Step: Access the Billing > Settings> Accounting> Daily;
  • 2º Step: Select Create; 
  • 3º Step: Fill the mandatory fields Name, Type (Payment Method) and Code; 
  • 4º Step: Save;

This error happens when you want to validate an invoice with a later date than the ones in drafts;

If you want to validate your new invoice while you still have an old one in drafts do:

1. Select the invoice and click in Edit
2. Select the option Force Opening> Validate
3. Confirm if the invoice got properly validated and if it's state is now Open; 

• When you create a VAT 0 invoice, you can't validate it, this happens when you don't define an exemption reason;
• To make this definition do:
• • 1º Step: Create a VAT 0 invoice;
  • 2º Step: Go to Other Information > Exemption Reason and select one of the options;

• If you get this validation error:
• • Can happen for two reasons
  • • It's not in the correct format, the SSN is composed by nine digits  AAA-GG-SSSS;
    • The SSN is not valid; 
    • • Para verificar se o NIF é válido pode usar o NIF ​ VIES ;

• If the warning There is no invoicable line appears:
• Happens when the item has the billing politic invoice delivered quantities;
• It's possible to check the billing politic in the item file, in General View > Billing Politic; 

SAF-T means Standard Audit File for Tax Purposes and corresponds to the normalized file with the goal of an easy exportation at any moment;

​ AQUI​

If you want to extract this file do:

1.  Access the Accounting/Billing> Reports > SAFT > Extract SAFT
2. Fill all the fields and then click in Extract SAFT.

• If the invoice has been already certified you can't legally change it;
• • You have to cancel the invoice and issue new one; 
• As an alternative you can double the canceled invoice and make the changes you need;

An invoice is a document sent from a seller to a buyer when it’s time for the buyer to pay for the provided goods or services. In the US, businesses are required to keep a record of all of their sales and income, which can come in a variety of forms including invoices and receipts. Therefore, an invoice is important for a business owner to keep a detailed record of their sales for accounting purposes, but also for the buyer in the case of any disputes.

An invoice is not mandatory for business-to-consumer (B2C) sales, so a payment receipt may be the only document you need to issue. However, if a customer (consumer) asks you to send them an invoice, you should issue one.

• In the US, there are no specific requirements for how you format your invoice numbers. However for accounting purposes, the numbers should be sequential and not include any gaps.
• Invoices may be required for certain business-to-business (B2B) sales, and if your business imports or exports goods. You should check with your state government for your local invoicing requirements.

• nine-digit number consisting of five digits, a hyphen, and four digits, which the USPS describes by its trademark ZIP+4. The correct format for a numeric ZIP+4 code is five digits, a hyphen, and four digits.

• If an invoice is Validated, has an associated payment and there is the need to cancel it you have to unbind the payment first;
• That movement is called deconciliation;

• When you validate a sale order and see that the items are divide in two or more pickings is because of the selected options when you created the sales order:
• • If you selected Delivery each item when it's available, pickings will be created as the items get available;
  • If you selected Deliver all items at once, it'll create a picking with all the items;

• It's because the invoice has the value 0;
• When an invoice is put in open it's because there is an amount that needs a payment;
• When  the invoice has the amount 0 and a payment is not needed, the invoice gets the payed state;