Once I talked about files on websites. Now I can firmly say that if you have something to have in them, they should definitely be present on the resource. For example, you can format your price list as a pdf file and make it an active link. That is, your potential client can save it for himself.

If you need to fill out any documents, for example, for the customer, dimensions and the like, then doc files as described above are also worth doing. And additional indexing by Google is provided. Similarly, tables. I am often asked about presentations. I think it is better to convert them into Google presentations and insert the code on the site. In case of display for any willing visitor on the resource. 

If you are making instructions for something, do not be lazy to create a PDF file and upload it to the site with the read button. In the future, this will give a very good result. Moreover, links in such files should also be created. Of course, we always remember about the size. Not everyone has good internet at hand.