Many bicycle tools can be quite expensive for an average tinkerer. On the other end some parts can be so hard to remove, that they do require some investment in tools to get the job done. E.g. to remove the fixed cup of an old road bike. Found this neat trick on Youtube for that exact problem, by "RJ The Bike Guy". Note he starts with an expensive electric impact wrench which works wonders if you own such a thing, but watch the video to the end where he shows a bit cheaper way where he uses some long breaker bar.