My next episode on Quantum computing should answer all your questions but generally, I don't think humans will be able to own a quantum computer for personal use in a long time - or even ever. They're simply too powerful and if they get into the wrong hands - they could start to become a problem.
I think if they are going to be implemented, they'll be used for large systems such as traffic lights as mentioned above. I believe google has one also, called DWave - which I imagine helped them with all the data they have (which is a lot).
I hope this answers all your questions. Don't hesitate to keep asking :)
I think you may very well have @mystifact ! But I will hold out for your next article! Though I do wonder if we will sound like the scientists in the 70s saying the same thing about computers that took up a whole room back then. Who knows! I'll be keeping an eye out! Cheers @ecoknowme