Hope you pay the rights to create those tracks or you could end up in a whole lotta legal trouble. Just cause you have the tools to creat karaoke songs doesn't give you the legal right to sell your tracks.
You gotta get the rights from the artist for the music, even if you record it using studio musicians. That is if you can get them to let you do it. I can name a few artists that would sue you if you even try.
you also need to pay for sync rights, and so on and so on.
All in all an expensive endeaver.
And besides why would I need your services when I can do it myself since I have all the tools.
Can't help but note that all four of your posts are really the same post.