Critics will point out the higher the cost of expert SEO, the more cost-effective Adwords becomes, but Adwords will only get more expensive, too. At some point, if you want to compete online, your going to HAVE to build a quality website, with a unique offering to satisfy returning visitors – the sooner you start, the sooner you’ll start to see results.
The world is mobile today. Most people are searching on Google using a mobile device. The desktop version of a site might be difficult to view and use on a mobile device. As a result, having a mobile ready site is critical to your online presence. In fact, starting in late 2016, Google has begun experiments to primarily use the mobile version of a site's content42 for ranking, parsing structured data, and generating snippets.
The ranking of your website is partly decided by on-page factors. On-page SEO factors are all those things you can influence from within your actual website. These factors include technical aspects (e.g. the quality of your code and site speed) and content-related aspects, like the structure of your website or the quality of the copy on your website. These are all crucial on-page SEO factors.