KarenC - Yes you still should create a mobile variant for your site. Mobile sites but nature of the devices used, specifically smart phones and smaller tablets, should be simpler with larger type and less images. I can view complex websites on my smart phone if I am using WiFi or getting a very strong signal, but if I am not getting a strong signal, then if a site is taking too long to load I am off to the next site.

You can have as many older versions on your computer as you like. And I may be wrong about some older versions but I believe you can have two versions opened at the same time to copy and paste from one to the other if you like.