一元到四百元的利息也太高了，不可能。如果是真的一元到四百元，后面应该有别的主线故事。讨债公司是不能另加费用的，你这个说法让讨债公司蒙受“不白之冤”。
下面是对讨债公司的约束：
15 USC § 1692F - UNFAIR PRACTICES
(1) The collection of any amount (including any interest, fee, charge, or expense incidental to the principal obligation) unless such amount is expressly authorized by the agreement creating the debt or permitted by law.
(5) Causing charges to be made to any person for communications by concealment of the true purpose of the communication. Such charges include, but are not limited to, collect telephone calls and telegram fees.
