Hi @Asterix ,
Question1
Were you referring to any Business rules associated to the QUOTE table?

Question 2
Can you please check the following Regular expressions for the character € :
/^\€?[0-9][0-9,]*[0-9]\.?[0-9]{0,2}/I
Test Runs: // Only for the character €
€123 - True
123€ - True
^([^\d\s]{1,}\s?[+-]?)(\d{1,3})(\,\d{3})*(\.\d{1,})?$
Test Runs: // For all the characters €, $, &
€123 - True
$123 - True
123 - False
&123 - True
I hope this might help you to adjust the RegEx as you wish.
Best Regards,
Shageesha