(Not to mention some webmasters will charge a fee to remove links ...)
Yes, there are a lot of hidden costs to hiring cheap "seo services".
@TotalWebsites - Have you ever gotten a manual action lifted purely with a disavow file? I haven't been doing a lot of work with penalties lately, but my understanding was that if you don't show some effort to actually remove links they get snitty and deny it. Though I guess if you document in the google doc who you tried to contact, when you tried to contact them, and that you got no response (or that the answer was a flat out "no") they might go with it (depending on your overall site quality and how bad the spam problem was in the first place ... questionable site + long history of spam = probably not so much).