Walls are eaier to do because you don't need to lay plywood underneath. If you have existing tiles, you can rip them off. Drywall may be torn at some places. You need to patch them up with plaster, which is easy to do. You need to sand the plasters down so the wall surface is smooth. No need to sand as smooth as you do if you plan to paint the walls. Then you lay tiles. You need tile glew for laying and then grout to fill in the gaps between the tiles. Don't let the unfamilair vocabularies to discourage you. It's really easy. Homedepot gives free lessons. You should check it out. You can finish most of the tiling jobs in a day. The Rona's also offer tile cutting. It's a dollar each straight cut. If you want, you can also rent a tile cutter. Tiles are easy to cut with a cutter.
If you are willing to do this yourself, you really should check out the free demonstrations at the Homedepot or Rona. It really takes 15 mintues to learn most of the skills you need to do the job, seriously.
I built my ceremic tile kitchen island and countertops myself. The carpentry work took some time but the tiles took me only half a day. It's not hard. You are tiling your walls and so there is no carpentry work.
