My clarification shall be limited only to the Service Tax issue since I am not an expert in VAT (Though I am not an expert of ST Too, but I think I can handle this one).
As far as construction and allied services are concerned, w.e.f. 01.04.2011, there is a clear provision under Rule 2 of the Cenvat Credit rules 2004 which states that No cenvat can be taken by any person in respect of WC service except a person who himself is engaged in construction service as a service provider.
Please see Rule 2 (l) of Cenvat Credit Rule, 2004::
(l) “input service” means any service, -
(i) used by a provider of 26[output service] for providing an output service; or
(ii) used by a manufacturer, whether directly or indirectly, in or in relation to the manufacture of final products and clearance of final products upto the place of removal,
and includes services used in relation to modernisation, renovation or repairs of a factory, premises of provider of output service or an office relating to such factory or premises, advertisement or sales promotion, market research, storage upto the place of removal, procurement of inputs, accounting, auditing, financing, recruitment and quality control, coaching and training, computer networking, credit rating, share registry, security, business exhibition, legal services, inward transportation of inputs or capital goods and outward transportation upto the place of removal; 27[but excludes],-
28[(A) service portion in the execution of a works contract and construction services including service listed under clause (b) of section 66E of the Finance Act (hereinafter referred as specified services) in so far as they are used for -
(a) construction or execution of works contract of a building or a civil structure or a part thereof; or
(b) laying of foundation or making of structures for support of capital goods,
except for the provision of one or more of the specified services; or]