You can get some idea by taking a quick look at some famous logos and the price tag attached to each:
Pepsi logo price tag: $1,000,000
The new Pepsi logo was designed by the Arnell Group in 2008.
Accenture logo price tag: $100,000,000
The new Accenture logo was designed by Landor Associates in 2000.
Glasgow 2014 Games logo price tag: $95,000
The Glasgow 2014 Games logo was designed by Marque Agency.
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