I have a hard time knowing where to invest. I'm a complete tightwad. That said, I have a photog friend in Nashville who told me recently that he's spending about $2k per month on advertising (google adwords). He and his wife does nothing but elopement photography. They're currently booking $20k-$30k per month. Just generalizing, it seems that 10% is a pretty good number to invest in marketing for your business. On my venue, I have a couple of improvement projects to get done then I'm intending to jump my spending to $1k per month, with plans to take that to $2.5k per month. You gotta spend money to make money.