This happened a few years ago, when I had more free time in the day & an 
unfiltered TalkTalk landlane that rang daily with scam calls from Microsoft or TalkTalk.
The phone rang and the person on the other end (We’ll call him John, he probably called himself Elvis or something) claimed they were from TalkTalk, John even knew my customer number. He told me he’d been monitoring my connection and my PC has been reporting errors that were caused by my faulty router. John said he’d like to replace my router, fix my PC & refund me £200 for the inconvenience. He was keen to show me the errors in my operating system so guided me to the event viewer to show me the issues I had.
John told me he’d sort everything out, I just needed to allow him to remotely access my PC & he’d fix my errors, pay my compensation & organise a router swap-out. I started up a Windows XP VM, John walked me though installing Team Viewer, connected to it then also installed SupremoControl which I hadn’t heard of before. John opened up the browser & navigated to a website that started with www.ttserviceuk which showed me a list of UK banks & asked me to click on my bank, the graphics didn’t render correctly, but I managed to click on Barclays, so that would do, a fake Barclays online banking login page appeared.
John now had full remote access to my (virtual) PC at this time so could have installed anything, including a keylogger & he asked me to logon to my banking site so he could transfer the £200 to me directly. I typed in a made up account number just as just as I pressed logon I disconnected the virtual machines network card so John lost connection too & couldn’t see my screen. I told him on the telephone that I’d checked my balance & logged out of internet banking, I then enabled the network card, re-establishing his connection.
John thought I had some security software installed on my PC that disabled remote connections when a bank website was logged onto, so he instructed me to uninstall any security software installed on my machine and try to logon to the bank website again.
I kept John online with me for over two and a half hours by randomly disconnecting the network, “accidentally” disonnecting his Teamviewer connection, mixing up browser windows & generally doing silly things.
I never did receive the replacement router but Johns friends called several times more & I gave them the runaround too.