Vat on software business

Dear All,

One of my client is engaged in Software Development Business. With
regard to the same I would like your opinion on the below points.

1) Whether VAT is applicable if he is preparing customized software as
per client requirements which he will not be selling in open market if
yes on what amount vat is applicable.(whether any composition scheme
is available)

2) Whether VAT is applicable if he prepare the software for sale in
open market if yes on what amount vat is applicable.(whether any
composition scheme is available)

3) Whether service tax is applicable in both the cases? If Yes on what
amount? (whether any composition scheme is available)

4) If at the end of the year, the software is still not completed how
to calculate value of WIP since there is no purchase for the same.

Thanks

Rupesh shah