I am here to help you accelerate your cultivation of expertise, deepen your impact, extend your reach, and increase your profitability. If yours is the path of the self-made expert, I hope to serve you as a teacher, connector, or coach.
You have two options:
1. Cultivate more valuable expertise
2. Increase operational efficiency
Those two options are, in some cases at odds with each other, but if you focus on #1 first you can use that expertise to drive #2 later. Or, you can ignore #1 and focus exclusively on #2.
#2 looks like productization. Ex: https://knapsackcreative.com/ You basically trade the occasional dramatic upside of custom work for the more consistent upside of standardized work, which lets you iterate your way towards a highly efficient operation and gain incremental improvements in profitability along the way.
#1 requires that you specialize. This does two things. It addresses marketing efficiencies by helping you answer the questions "who are my best clients?", "how do I find and connect with the?", and "what job are they wanting a website to do and how can I help them do that job better?". Second, it allows you to cultivate exceptionally valuable expertise.
About expertise: Skill gets it done; expertise ensures it has meaningful impact for your client.
If the most you've been able to earn from building a website for a client is $2,000, you probably have skill but lack expertise.
Specializing in a market vertical (ex: manufacturing, retail, etc.) or a type of website (ex: e-commerce, membership sites) will accelerate your ability to cultivate expertise. Repeated exposure to similar-enough situations will allow you to move beyond offering just skill to offering impact, for which clients will happily pay higher fees.
Regarding cash, here's a price per/subscriber comparison of the major marketing automation platforms: https://dripsherpa.com/how-much-does-drip-cost-compared-to-mailchimp-aweber-active-campaign-infusionsoft-ontraport-marketo-hubspot-and-mad-mimi/
I'm a fan of Drip for your use case because it's easy to use and hits a great price point.
But the larger question I'd urge you to consider is this: What one place in your sales funnel would implementing marketing automation reduce friction or increase conversions?
I think it's easy to think of marketing automation as a magic bullet, while in reality it is a powerful toolkit that requires an investment of expertise and effort to get the most out of it.
If you start *small* with marketing automation you're more likely to have a successful first project that provides the monetary and emotional ROI necessary to move onto a bigger project.
I have landing-page content marketing opt-ins that routinely perform from 30 to 40% (http://cl.ly/image/1i3z1K3z1K3b) and one of my clients has a site-wide opt-in converting from 6 to 10% of site visitors.
The key to numbers like that are a strong match between your site traffic's intent and the opt-in offer. As an example, any time I guest on a podcast, my answer to "how can people find out more about you?" is to send them to http://positioningcrashcourse.com (which is not about me at all, but is a premium content resource that serves as the mouth of my funnel). That's the page that converts as well as 40% and normally converts at 30 to 35%.
I call this "getting your own traffic", and it converts at very high numbers relative to paid traffic or even organic search traffic.
So if you approach traffic generation in this way (or another way that sends warmed up, qualified traffic to a landing page), your 2% traffic --> list number is potentially way off.
The other reason why you're seeing so many others talk about content marketing as the holy grail is because it _is_ the holy grail... of building trust and demonstrating expertise.
It is not the best way to drive short-term sales tho.
But if you have a more medium to long term view, content marketing is a great way to attract leads and nurture them towards being ready to buy.
If you're an author (who is by definition sloughing off content all the time), this is a viable strategy because you're in it for the long haul with your audience, and time is on your side (see "Your First 10,000 Copies" for more details). If you're trying to drive e-book sales for minimal cost, it probably is not a great strategy.