I am working on an dapp (private blockchain) wherein users can exchange fiat currency for a token. The token can then be exchanged for particular goods and services, for example: groceries, health, transport, bills and so on. At the outset of the transaction, the sender can opt for the token to be linked to particular good or service. Alternatively, they can create a blank token, and have the sender decide what goods/service to link the token to.
The purpose of the application is to facilitate trust between two parties wherein the sender requires the receiver to spend the funds for a particular purpose. For example, an individual working in Italy can send back a set of tokens (2x grocery, 1x transport, 1x bill) to family back home in South Africa, who can then spend it as requested.
With the above outline in mind, I wanted to ask how an individual token would be valued. Given the nature of the system, it doesn’t seem sensible for the token to be volatile and traded on the open market. Furthermore, given the fact that the token to be consumed within the context of business partners (eg retailers, public transport services and utility companies => who can then exchange it for fiat) all across the world, how do I go about determining the exchange rate of token => goods, services in each country? Also, do any dapps exist which perform this function?