The IDR and HZ use two very different forms of currency, which makes exchange difficult or impossible; their interactions, then, rely entirely on barter.
Within the first year after batwara, both governments on the Rann of Kutch recognized the need for a currency system. Generally, ships-at-space maintain debit accounts for their crew, which update over communications networks when possible; even those on deep-space missions update accounts via ansible, allowing crewmembers to purchase small items at the ships’ commissaries. Cut off from the wider Bharatavarsha economy, both governments established systems that would allow them to develop their own economies and allow them to flourish.
HZ’s currency is the closed rupee. Freezing the existing bank accounts of its crew (promising to unfreeze them upon rescue, which ended up never occurring), HZ established salaries for its various ranks and positions, and eventually cost-of-living charges for use of the mess and sleeping quarters, provisioning, and the like. The system initially resembled the use of scrip, only usable at centrally controlled commissary outlets, but eventually organically expanded to resemble a true monetary system, with individuals accepting money transfers for goods or services from other individuals. Due to a lack of physical resources, the closed rupee has never been printed into physical form, but transfers entirely through the use of individuals’ tabs.
The IDR’s currency system is more radical, and operates almost like a reverse wage system.