IMPORTANT tip for using ad control facilities: Some ad control services will want you to sign a long term agreement. I doesn’t do this unless the promised money was mind blowing. However, and here is the kicker, extravagant promises means the number of ads and annoyance level is very, very high. If you commit long run, you may lose handle over this, which is something I don’t think I could surrender.
The fact is some types of ads can or will shortly hurt SEO i. e. interstitial ads. In my view, ads that hurt search engine marketing aren’t worth it at all unless you truly don’t care about search engine traffic.