对于每一笔交易，你要支付一个基准授权费（0.15—0.30美元）再加一个额外的百分比费用。

For every transaction, you’ll likely pay a base authorization fee ($0.15-$0.30) plus an additional percentage.

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费用按固定的费率收取，不是按百分比。

Fees are charged at a flat rate, rather than on a percentage basis.

《柯林斯英汉双解大词典》

Go - ForIt将把胜出的投标者与需要服务的客户配在一起，并按完成差使的报酬的一定百分比收取费用。

Go-ForIt would match up the winning bid with the customer in need and collect a percentage of the fee paid for completion of the errand.

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