Sell seo services to local businesses - how?

Don't sell "SEO", most owners don't care what it is. Sell more calls from Google. What works best for me is sitting with them and searching their main service plus their town. Their competitor is in the map pack, they're not. That does the selling. Then offer something fixed and easy to say yes to: tidy up the Google Business Profile, fix their main service pages, get citations consistent, set up a simple way to ask customers for reviews. After that, a monthly retainer. Never promise a ranking position, that's the client you'll lose in month three.