The function default_select() in the file “/invoiceplane-v15/application/modules/invoices/models/Mdl_invoices.php” includes queries the database for the value of ip_users.user_iban.
Unfortunately, the same function default_select() in the file “/invoiceplane-v15/application/modules/quotes/models/Mdl_quotes.php” does not query the database for this information, hence, it is not available when you type $quote->user_iban.
@kovah to me this is a bug: the default_select() in the quotes model retrieves less information about the user from the database than the same function in the invoices model. These are the missing lines of code:
Should I add all of them to a pull request? Maybe we should just replace all those lines with ip_users.* to retrieve all columns from the ip_users table instead of having to update the models each time that table is modified. For instance, this is what is done for ip_clients.* and/or ip_invoice_sumex.* in these queries.
to your “invoiceplane-v15/application/modules/quotes/models/Mdl_quotes.php” between the lines ip_users.user_tax_code and ip_clients.*, but just in case, make a backup copy of the file before editing it. And do not forget to tell us if that solved your problem.