OS Commerce Website

We are looking for a reliable Freelancer to carry out a few small tasks on our Oscommerce website:-

1. We have set Tax up on our the site and all works perfectly as admin. As soon as any customer is logged in (as a UK customer) it does not add tax. We are sure it is something simple we are missing.

2. On our Invoice Template, one graphic needs changing (graphic supplied).

3. Also, on the Invoice Template it states "Order Number", we would need this changed to "Invoice Number"

4. We also would need a VAT Number added at the base of the template and statement "VAT Charged at ......."

5. We noticed we have a small issue with "Shipping address" on the invoice. We need to be able to change the Shipping address (within admin) so that the "SOLD TO" is not affected on the invoice but just the "SEND TO" changes. This would need to work when we change the Shipping address in the admin section and also if customer changes delivery address themselves.

Thanks for looking!