The most affordable - and effective - approach to Internet marketing is with inbound tactics. But without a solid strategy your results will be less than stellar.
There is a temptation for small business owners and marketers to simply rely on "word-of-mouth" and referrals through social media channels. For too many, this is what constitutes their "affordable" Internet marketing approach. The problem is that, first off, not that many people are probably going to talk about your business.