I've been asked to put a new vinyl tile floor over an existing vinyl floor.
If the old floor is in good shape, I'm considering using a floor leveler
product first then thinset mortar before using the peel and stick tiles.
Option 2 to install 1/4 lunan with ringnails then applying thinset before
installing the tiles.

My question is the thinset overkill ?
Any other suggestion ?

Thanks
Dick