Tile – Cutting notch out of tile- least wasteful/ fastest option

When I used to do a lot of these for a building/renovation company, the approach our foreman recommended was to assume the drywall will need replacing anyway and just rip it out. That would let you remove that entire panel in 45 minutes, and then you can just pop a new piece of drywall in, which is another 15 minutes.

As you can see from your 45 minutes, the drywall is going to be ruined, so just bite the bullet - get in behind it and pull it all off. The use of a crow bar and hammer may help here.

If you are wanting to keep the tiles on the adjacent wall, make sure you have cut a gap in at the corner so you don't rip it out as well.

Also, make sure you have something over the drain, to avoid it becoming clogged (I know - sounds obvious, but people do forget)

Updated to incorporate comments

• Cement board and a vapour barrier are the only suitable backing for your tiles here. Drywall shouldn't have been in there to begin with.
• Watch out when hammering around plumbing, to avoid water leaks adding to your worries!

You need a diamond tile saw, where you put the tile on a platform and slide it past the water-cooled blade. They are fast, precise and good for the hardest porcelain tiles. Expect to pay $300 and up. Straight cuts are the easiest. To cut out a square corner, make the two cuts with the tile upside down. The back of the tile will be a mess, but the business-side will be tidy.

If you want the cut edges to be velvety smooth to walk on or rub skin against, use some damp 400 grit wet/dry held at a 45degree angle to the sharp edge.

Score-and-snap tools are fast for cut edges that will be hidden by a baseboard.

Cheaper saws where you push the tile through (like a table saw) are OK, but not as fast and versatile as the sliding-table models.

For round holes for shower heads etc, use a diamond hole saw. If the tile is porcelain, submerge it in water on a bit of plywood while making the cut.

For rectangular holes for electrical boxes, use a diamond hole saw for the four corners, then use the tile saw from the back, like a mitre saw.

The wet diamond blade is pretty amazing - it will cut through tiles but is fairly safe on fingers. You can hand-hold tiles for tricky trimming without too much danger. (at least so far!)