The couple of calls I've had were from setups with a 1st and 2nd level "support" structure. The 1st level person sells you the pitch and gets you to check the error logs etc and agree to being "helped", then they transfer you to a second level person who talks you through running remote access and f***s fixes your computer. 2nd level are likely less numerous and more highly paid, so the trick is to make it through to the 2nd level as quickly as possible to maximise the cost of wasting their time. I had one totally lose it and spend almost 10 minutes abusing me for wasting his time...