Sometimes very little, sometimes a lot. Hubspot, for example, may charge 10X more than most email marketing tools but they offer an all-in-one marketing & sales platform that includes everything from landing pages and live chat, to a social media management tool and CRM. On the other hand, ActiveCampaign offers an enormous amount of value while remaining one of the most affordable email marketing tools on the market.
Address subscribers by name. Personalized emails are more successful. Buffer also suggests to personalize your emails based on need by sending emails that meet different user expectations. This makes them more targeted and more likely to be successful. Some studies show that educating and segmenting your audience will boost your click through rate on emails by up to 50%.