No such thing as wallpaper for floors, but there are a few good solutions for water resistant flooring. Pvc, vinyl, linoleum, epoxy or polyurethane paint, for example. I see you live in India, I have no idea what products can be bought there.

well i do trust him....but I m just concerned about the wallpapers....haven't really used them nor have seen anyone with that in the locality.....that's all....

http://www.stevesblindsandwallpaper.com/wallpaper/productdetailpricing.aspx?pn=CX1211&ctg=1885&rkg_id=h-a7c5f2e064cae264e08d06eb027be207_t-1456200827&adpos=1o1&creative=48192656442&device=c&matchtype=&network=g&gclid=CjwKEAiAgKu2BRDu1OGw3-KXokwSJAB_Yy2QWK4nTKLJgbsugtPh5LH7c8hwwNPCvoZUnS_HtC0mDBoCj1Tw_wcB

Hello Sir, I do not understand- what do you mean by "changing the wall Designs." For coloring/wall papers/textured painting it is better to have finished wall. For wall cladding/tiling it is OK to have a non finished wall as well as they require a rough surface. For changing the tiles, its quite a messy, and wasteful expense. Rather, you can give the tiles of your choice to builder to install on the first go itself. Some builders don't allow such requests but others would happily do so. Some others may even offer a discount for not using their tiles. Same thing with paint as well you can give your colors to them to paint if you are not happy with white. Thanks, Nitin CORNERSTONE DESIGNS Bangalore.