Hi
To get a mobile version, you do not need to have a new website. Your existing website can be made responsive so that it is optimized for viewing in both mobile as well as tablet device. If you would go for a separate website, it would not only cost more at this stage but throughout would cost more while updating the website. As any of the tasks will be done on both desktop as well as mobile versions, which would simply double the efforts.
So a better approach is certainly to convert your existing website into responsive. Though for that, we need to know the URL of your website so that we may do feasibility testing as well as may evaluate the efforts.
Please open PMB to discuss this further.
Kind Regards
Sam
OweBest