You may have heard people talk about quality backlinks because search engines have started looking at your backlinks to see how much value they hold and whether they are manipulative or authoritative in nature. They have even started to punish websites that obtain manipulative backlinks by removing them from their indexes. It is therefore more important than ever before to be careful with your backlink types and avoid poor quality backlinks at all costs as they could easily ruin your ambitions to see your online business pick up.
You should be working towards obtaining quality backlinks such as the ones that come from authoritative domain extensions. Infact, .edu backlinks have always held power and you could see quick ranking improvements however there are certain conditions associated with it. Firstly make sure there aren't too many outbound links on the page that you obtain a backlink to your website from. This is so that your backlink profile remains clean and reputable. Secondly, make sure you obtain backlinks at a good frequency as opposed to building thousands of backlinks at once and then doing nothing for the rest of the foreseeable future.
Also when hiring an SEO company, make sure you find out whether you are dealing with an SEO affiliate who would take your business to another company or whether you are working with the service provider itself. This would help you save time and money when picking a company to work on your website.