Service tax registration - centralized

Dear Members,

We are service recipient registered under Reverse Charge mechanism of different services and receive services in different locations (Approx 50 Locations) from where we operate our wholesale businesses.

Whether we have to take centralized registration under service tax or separate registration of each location under following conditions:

1. The books of accounts are maintained separately in each location and at the end of the year we transfer all balances of accounts to the head office to consol the balance sheet and profit and loss accounts for finalization.
2.  The Services we receive like Rent a Cab, Security/Detective Agency, Legal Services, GTA etc at separately in each location.
3. All Vouchers and invoice bills, supporting etc are maintained at branches.

AS PER SERVICE TAX ACT, IF THE COMPANY HAS CENTRALIZED BILLING SYSTEM OR CENTRALIZED ACCOUNTING SYSTEM AND SUCH CENTRALIZED BILLING/ACCOUNTING SYSTEM ARE LOCATED IN ONE OR MORE PREMISES. THEN THE COMPANY HAS TO TAKE CENTRALIZED REGISTRATION OF THAT PREMISES FROM WHERE SUCH CENTRALIZED SYSTEMS ARE LOCATED.

 AS PER RULE 4(3A) OF SERVICE TAX RULES, IF ASSESSEE DOES NOT HAVE CENTRALIZED BILLING/ ACCOUNTING SYSTEM, EACH PREMISE OR OFFICE WHERE TAXABLE SERVICE IS PROVIDED/RECEIVED WILL BE SEPARATELY REGISTERED.

QUESTION: Our requirement is that, we have not centralized accounting/billing system and having more than 50 locations/premises where we received the services. Is it possible to take centralized registration of the Head office premises where all books of accounts of branches are console yearly basis?  If not, is there any other way to register under centralized registration? Because it is practically impossible to register each premise and do all compliances of service tax separately.

Thanks in advance