The SEO advice you find online is almost always aimed at big businesses or ecommerce sites. It does not apply to a plumber in Earl Shilton or an electrician in Hinckley. Local trade SEO has its own rules, its own ranking factors, and its own best practices.
A proper SEO strategy for tradesmen focuses on local search visibility, Google Maps rankings, and converting local searchers into paying customers. It accounts for the fact that most of your customers search on mobile, they want someone nearby, and they decide quickly. Your strategy needs to be built around that reality.