Taxability of joint venture cash calls depends on whether contributions are capital or constitute payment for services, affecting GST liability. Confirms that GST treatment of supplies between an unincorporated joint venture and its members follows prior Service Tax principles: whether cash calls are taxable hinges on the JV agreement and the nature of the payment. Cash calls used as capital contributions to acquire JV assets are transactions in money and not treated as consideration for services; payments that reimburse an operating member for use of its machinery or performance of activities constitute consideration and amount to a taxable supply of services. Each JV agreement must be examined factually to determine GST liability.