tile on walls is $4 square foot. And that is the minimum some guys try to get up to $10 a square foot but $4 will be the low cost.
15 by 14 is 210 Sq ft which is 23.33 yards If installation is 5$ a yard Pad is 3$ a yard. Carpet you get a 12 $ a yard carpet (med. Grade) So right at about 500$ is what you'd be looking at