Formally validate Billing Details

Let's face it, customers do not put so much attention when they register on WHMCS. Here is how you end up with clan names in place of Company Name, passport ID as VAT Numbers or even worse with customers who refuse to update their profiles with new details you strictly neeed in order to comply to new regulations.

Much of the work of every administrator is to make sure that such details are always correct but investing so much efforts into spotting wrong details doesn't sound so funny. Implementing ways to automate all these checks isn't impossible but at the end of the day there's always something more important to do. That's how this boring task of checking Billing Details has been procrastinated by all of us for years.

Enough is enough. We're implementinmg various techniques to make sure that Billing Details provided by customers are correct. I myself no longer want to deal with tickets regarding billing.

As you can probably imagine it's frustrating but somebody has to do the job... and the "winner" is... Katamaze! Ouch. I won't share with you all the details but we're making sure that the following criterias are met.

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Individuals from Italy. Codice Fiscale (aka Tax ID) is mandatory and must be formally valid (16 characters, firstname and lastname matching the first 6 characters of Codice Fiscale).

Companies from Italy. Partita IVA (VAT Number) is mandatory and must be formally valid (11 characters, numbers only, valid security number). Codice Fiscale (Tax ID) is also mandatory and must correspond to Partita IVA. Codice Destinatario for Electronic Invoicing is also required and must be valid (PEC address, SdI code 7 characters or PA code 6 characters).

Sole proprietorship or sole professional from Italy. Partita IVA and Codice Fiscale are both mandatory and must be valid. Codice Destinatario is also required and must and must be valid (PEC address, SdI code 7 characters or PA code 6 characters).

Organizations, Public Authorities, Government. Codice Fiscale is required and must be formally valid. Partita IVA is optional but must be correct when specified.

Intra and Extra EU individuals. Tax ID (passport ID should be allowed) is required.

Intra-EU companies. VAT Number required and formally valid according to formats of each Revenue Agency of Europe (sounds funny uh?). Tax ID is optional.

Extra-EU companies. VAT Number is required. No further checksare  required.

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We want you to notice that this system works proactively. As soon a customer logins, we check if his Billing Details are correct. If they're not, we redirect him to a new page from which he's forced to update his information otherwise he can't proceed to any other page (contact, tickets and few more pages "whitelisted").

Let us know if we missed something in the comments!