First, we, RVglobalsoft, are a software provider not a hosting provider company. So we don't have domain for you to register(purchase). We are really sorry about this.

And RVsitebuilder can be purchased and installed only by hosting provider companies who will provide this website building tool on their control panel servers.
Thus, if you're a user, who doesn't own a server by yourself, you will not be able to purchase RVsitebuilder directly with us.
This case, we would like to suggest you to find a Hosting Company that provides RVsitebuilder in their package. Then you can both register domain name and use RVsitebuilder to create your website through their control panel.
If this is done, to move your current website from Wix to RVSitebuilder will mean to start over again for the entire website due to the structure between Wix and us are totally difference.

Any further questions you may have, please feel free to let us know.