Central Registration in Service Tax

Hi Freinds,

I' m working with a Engg Consultancy in Gurgaon. We are registered service provider in delhi. Recently we have bagged a new project in some other state.

The query is Whether to take a separate reg number for newer state or keep the existing reg number & add another unit to it. Which method would be preferable from service tax point of view??

Please also provide info on best way to maintain books of accounts for the purpose of Company Law and Income Tax, so that records of the site can be easily merged with the company's main accounts??

Please provide with advise. ASAP

Thanks & Regards

Sushant