When you buy SEO services from any good digital marketing agency or SEO specialist, you should expect them to send you a monthly web marketig report. These reports basically tell you how you site is performing that month, and will show you the progress your site is manking in the search engine rankings over time.
Some key things to look for in your report could make the difference between selling a huge quantity and not selling anything. We think these are the key items in any good report:
Rankings statistics: you should have a clear idea of where your site is ranking for each of your keywords, and you should be able to see progress. It is important to know the rankings so you know which keywords you need to push more than others.
Analytics stats: things like visitor numbers, type of device used to view and page views will give you a valuable insight into the behaviour of your guests so you are aware how they are thinking.