Shall we add engaging and useful FAQ content in all our pages or rather not because of duplication and reduction of unique content?

[lcourse]

We are considering to add at the end of alll our 1500 product pages answers to the 9 most frequently asked questions. These questions and answers will be 90% identical for all our products and personalizing them more is not an option and not so necessary since most questions are related to the process of reserving the product.

We are convinced this will increase engagement of users with the page, time on page and it will be genuinely useful for the visitor as most visitors will not visit the seperate FAQ page. Also it will add more related keywords/topics to the page.
On the downside it will reduce the percentage of unique content per page and adds duplication.

Any thoughts about wether in terms of google rankings we should go ahead and benefits in form of engagement may outweight downside of duplication of content?