Forum Moderators: open
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I have found [google.it...]
but it is for foreign searches....
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fabrizio
The only way I know of is to set up an Adwords campaign. First you get the guesstimates from the programm. But more reliable and important are the figures you get from a weeks or two of experimenting.
If you resort to low bids, and make your terms very specific the money spend is rather low, the knowledge gained rather high.