If you've ever tried pulling off a piece of vinyl baseboard, you've probably discovered it's nearly impossible to do without damaging the wall behind it. That's because the vinyl usually is glued on with a specially formulated adhesive. An electric heat gun will help you remove it safely.
Open all windows and doors in the room for adequate ventilation. Slip on heavy leather work gloves and set the heat gun temperature to medium. Then find the end of a length of baseboard or a seam between two lengths and hold the nozzle a few inches away. Move the gun back and forth over a small area for about 30 seconds to soften the adhesive. Then insert a wide-bladed putty knife behind the molding and gently pry it away from the wall. If the molding is still stuck, apply more heat and try again.
Keep heating and prying along the molding until a section breaks free. Once the baseboard is off, use the heat gun to melt the adhesive on the wall. Then scrape it off with the putty knife.