One of the best, quickest and cheapest ways to improve your
SEO is to have actual content on your website - even if it is a shop.
By having articles on your website that correspond to well researched key words and phrases, you'll instantly improve your ranking.
I do a lot of work for clients who are heavily involved in Virtual Real Estate - Website Flipping ... that is, buying crappy websites, fixing them up so they have more traffic and are making money from Google Adsense and Products ... and then selling them for a significant profit - so I've learned a LOT about how to do this just from doing it for them.
I think - like everything in business - where most soloists struggle in this area is in STRATEGY.
Soloists have a real tendency to just kind of flit from one thing to the next - to dabble in things - and then wonder why they don't work.
It's important to have an online strategy. To know exactly what you want and to not get distracted by things that don't get you to your outcome - no matter how interesting they are or what a great opportunity they are!