Legal problem with bill and custom fields?

[diri]

Watching forum here I stumbled over http://forum.virtuemart.net/index.php?topic=143719.0.

Whenever something is printed on bill (like color and / or size of product X being bought) it has to be saved for years according legal obligations for proper accounting in several countries. It must be possible to re-print original bill (marked as re-print) in this time.

Sad enough there is no version in thread but, thread mentioned above points to not behaving like needed:

Change data of product X - bill seems to change because data of bill are not being saved for itself. It looks like there are references to product's "live" data only.

Is this true or did I look wrong?

When we are at it:
How is behaviour when default tax rate is changed (read: edited, i.e. 21% instead 19%) without adding a new entry for new tax rate?

Is DB kind of over-normalized?

[Jörgen]

I don know how others do it but I save all the invoices for the stipulated five years for bookkeeping purpose.I have so far not been bothered by these issues, because I have not done these kind of changes to my custom fields. The invoices are created and saved as PDF and should be intact, creating a new invoice would simply not be correct, So there should really not be any problems with this. Or should there ?

Jörgen @ Kreativ Fotografi

[AH]

I would not expect VM to handle every instance of accounting or business law for you
My suggestion:-

Use PDF's for invoices.

Dont change invoices after issued.

Store Pdf's for the required time.

[GJC Web Design]

also as I understand the pdf u create is never deleted/altered ( unless you manually delete it from the folder )
If changes are made in the order admin a NEW pdf is created  -- the old one is left intact

[diri]

I'm used to save PDFs for 10 years according tax law and GOB in Germany and have bills stored in almost un-normalized (tables bill and bill-details line by line) to be on save side but, nevertheless it's an interesting point about relational DBs and behaviour of customers.