Not Teamviewer. That's not a free program.
Maybe skype.
I'd be willing to test something open-source like TightVNC.
The only programs I find the need to pay for are games. Everything else has a open-source/free alternative. GIMP, Inkscape, Blender, Atom, Audacity, Mumble, foobar2000, IrfanView, MSI Afterburner, etc.