Work contract under composition scheme

Dear CA Clubindias Member,

I have a shop where I am doing Engineering Job Work.( Supply of Material and Labour ) as per requirement.

I have registerd under MVAT - Work Contract Composition Scheme.

Now i am billing prepare as follows :-

If Supply of material & Labour - I charged 8% VAT on total Value

If Supply of Only Material - I Charged 8% VAT on Total Value

If Supply of Only Labour - I Charged 0%

I just want to know, when i issu a labour charges bill at that time i dont charged VAT, but can any one let me know the limit of this type transaction ??

Till, how much limit, i will prepare this type of bills, or When i need to take service tax registration.

Please help me.

Shakir shaikh