Aged domains with authority (high PA or DA or having high quality links pointing to them) are very useful for ranking websites and videos and are the most powerful links you can possibly get.
One of the most common uses of expired aged domains is to build a PBN (private blog network). All that is is a fancy name for a network of expired domains that are all pointing at the sites and properties that you’re looking to rank.
PBNs are the same concept as guest blogging…but in this case we’re picking up those powerful domains so that we can control them. The big issue with guest blogging was that you would put in all this time and effort writing a quality article…but then maybe months or years later the site would go offline.
With PBNs you have all the control.
So, while there are other expired domain tools and finders out there, I would highly highly recommend investing in Domain Reanimator instead. It’s going to save you a TON of money in the long run.