It all depends if there is room for arbitrage, meaning if you spend $100 will you make $150 or $200 or whatever your conversion rate would be for your business. That requires that you need to have some sort of knowledge on how to create an adwords account, selects the copy for you ADS (text or display ads), select if it is search or Google's display network and then run the ads by bidding on keywords or the alternative targeting methods google offers.

Run $50, $100 or even $500, target specifically based on geo location, target age and be sure you have the proper tools on your website to measure conversion. That is, you know how to build url addresses that track when you make a sale? get a call or whatever the activity you are trying to convert for.

I happen to have a free $100 credit on google adwords: hopefully no one will read it before you do :)

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And if you want to test other growth hacking ideas more than happy to hop on a call :)