add a seperate mobile version of a website into current wordpress.

Maximum budget is $50 We have designed and developed a mobile version of our client website. They currently have desktop version running with wordpress. We want to incorporate that mobile version in the same wordpress installation and add codes so the mobile version shows up when someone access from mobile and desktop version shows up when accessed from a desktop/laptop. Now both website will have to be independant of each othere so that portfolio or any other page on desktop version can be updated without affecting the mobile version and vice-versa. We are not asking for RESPONSIVE LAYOUT. the Mobile version is completely seperate. Maximum budget is $50 as there is nothing to design or develop, you just gotta make both version work independently but still being part of the same wordpress installation.