I have a custom shower made from travertine tile that the previous homeowner built himself. It was in great shape when we moved in but soon after the tiles on the shower floor started to "pit" and the grout lines started to "erode". In doing some research I found that travertine is not really recommended for use in very wet places. A year or so ago I tried to repair it by filling the "pits" with grout and re-grouting where the grout lines that were eroding and then sealing it. It looked ok and it seemed to work....for a while. But now the tile is deteriorating rapidly again to the point that there are a couple major cracks so it's just time to replace the shower floor. I've found several porcelin tile products that replicate the look of travertine so I'd like to just replace the shower floor tiles with these instead of re-doing the entire shower/bathroom. I'd like to do the work myself but never really done any tile work so I'm looking for advice. My main concern is how to properly remove the old tile, what I'm going to find once I remove the old tile, and how to prep the sub floor for the new tile. Oh, and this shower is on the 2nd floor. Any advice would be appreciated.