Respectfully disagree....You can still start SEO marketing and PPC (pay per click) doesn't have to be a part of it. I hired an SEO company for $400 a month that took my site from no rankings to top 5 in rankings for certain keywords/key phrases. It took 4-6 months to get there but it's affective.
SMO is important but you also have to be careful. It can actually hurt you if the feedback in social media is negative about the site. Not saying it will be, but it could.
SEO finds people that may be looking for deals actively and ready to buy. SMO exposes the product or service to friends/family etc that are not really actively looking for that product or service at that time.
Bottom line is that they are both different but important. It's debatable by some as to which is better but it really depends on what type of business you are in.
Being that this business is 100% reliant on the internet to make money, he should be doing both in a massive way.