I have removed 30 yr old carpet and pad from concrete floor in basement bedroom. There is some sort of adhesive where the pad seams were. I put plastic over the concrete part of floor for a month and no moisture was evident. My questions are (1) do I need to remove the adhesive, if so how? (2)Do I need a vapor barrier? The kitchen 20 x 25′ has glued down carpet, so a lot of adhesive. This abuts a carpeted and pad area also to be removed. (3) where on the web ( or eleswhere)  is a reliable nonbias reviews for locking vinyl plank flooring?

There are alot of places for installation, but none on how and why  to prep the floor, subfloor.

Thank you, cmm