curl --request GET \
  --url https://api.exchange.coinbase.com/loans/repayment-preview \
  --header 'cb-access-key: <api-key>' \
  --header 'cb-access-passphrase: <api-key>' \
  --header 'cb-access-sign: <api-key>' \
  --header 'cb-access-timestamp: <api-key>'

{
  "before": {
    "open_loan_value": "<string>",
    "collateral_value": "<string>",
    "collateralization_percentage": "<string>",
    "available_to_borrow": "<string>",
    "available_per_asset": {},
    "withdrawal_restricted": true,
    "credit_limit_value": "<string>",
    "available_credit_value": "<string>",
    "collateralization_percentage_open_only": "<string>",
    "pending_loan_value": "<string>",
    "initial_margin_percentage": "<string>",
    "minimum_margin_percentage": "<string>",
    "unlock_margin_percentage": "<string>"
  },
  "after": {
    "open_loan_value": "<string>",
    "collateral_value": "<string>",
    "collateralization_percentage": "<string>",
    "available_to_borrow": "<string>",
    "available_per_asset": {},
    "withdrawal_restricted": true,
    "credit_limit_value": "<string>",
    "available_credit_value": "<string>",
    "collateralization_percentage_open_only": "<string>",
    "pending_loan_value": "<string>",
    "initial_margin_percentage": "<string>",
    "minimum_margin_percentage": "<string>",
    "unlock_margin_percentage": "<string>"
  }
}