Invoice templates

[Jackie2009ws]

Iam thinking about ss it possible to customise the PayPal invoice template to add basic features such as invoice number, date, prefix the telephone number with Tel. (for instance), add a fax number etc? The default template is just too simple. I can see workarounds using the Note field, but all I am trying to do is produce a legal (as far as UK tax authorities are concerned)VAT invoice for customers. Thanks.