The surface area of the four pillars is 0.6*4.8*4*4=46.08 square meters.

If you use 20CM*20CM tiles, you need 46.08/(0.2 * 0.2) =1152, so you need 1 152*2=2304 yuan.

If you use 0.3M*0.3M tiles, you need 46.08/(0.3*0.3)=5 12 tiles, so you need 5 12*3.6= 1843.2 yuan.