Hey r/entrepreneur, just wondering what your tips would be on the best, affordable small business marketing solution?

I have advertised from posters and flyers to word of mouth and business cards, and yet I (happily) maintain the same flow of clientele. Does anyone have an idea of what would be the best, most affordable small business marketing solution? I run a technology solutions company (specializing in web design, SEO, & technical consulting) that works mainly as a telecommute company.