When fetching or creating transactions, the amount, fees and max_fees values are always expressed
in the lowest available unit, also known as the base unit: satoshi for Bitcoin, wei for Ethereum,
mutez for Tezos, etc.
You can inspect the units available via a call to GET /accounts/<id>/currency.
ℹ️ Token transfer transactions on Ethereum, Polygon, or other EVM networks: the
amountvalue is expressed in the ERC-20 base unit, but thefeesandmax_feesvalues are expressed in the network currency used to pay for the transaction fee (ETH for Ethereum, MATIC for Polygon, etc,).