This highly depends on the industry and the country the parties are from. Each country and each industry has different rates.
Finder's fee ranges from 3% - 10%.
Real estate agent's fees range from 0.5% - 2.5%
Commodities deal broker fees can range anywhere from 2% - 20% - it all depends on the deal and the value that you're bringing to both sides. The higher the value, the higher your fee may be. Either way, I suggest you sign both sides on a 'finders fee' or "broker" agreement
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