Tax liability timing for development-rights and construction-service exchanges: state tax arises on transfer of possession by conveyance. Notification under section 148 fixes state tax liability for (a) suppliers of development rights paid wholly or partly by construction service and (b) suppliers of construction service paid wholly or partly by development rights; in both cases the liability arises when the developer or builder transfers possession or the right in the constructed complex, building or civil structure to the person supplying the development rights by entering into a conveyance deed or similar instrument.