Hi Milen thank you for the reply.
When we purchased the property we were no issued a BULSTAT card. Having looked through our documents I managed to find the BULSTAT number which was on a document written in Bulgarian, this is the only documentation we have which has this number on it.
The 'accountancy company' I have approached to take control of my end of the year tax, I believe is bulgrian, however they have a UK web site, but it is not up and running. I have asked them for their contact details in Bulgaria ie address, fax, web address etc etc, however they have not given it to me. At the moment they want my BULSTAT number so they can check to see what my taxes are in order for them to proceed.?!! Hope this makes a bit more sense than my last email.