Thanks for the photos!
Yes, the idea you have would work fine. I would also suggest sliding door and back to wall toilet. The space is proabely tight when you are trying to close the toilet door.
The question I have is what would you do with the rest of the floor? When the shower/ toilet floor is tiled, are you planning to tile the rest of the laundry floor and have a contious surface?
You could also have the shower area fully tiled and the rest just skirting.
First week would involve preparation - demolition, brickup, plumbing tubout, screeding and waterproofing .
Then a second week would involve tiling the floor ( 1 day) and then tiling the walls (depending on what you decide). After the tiling is done and grouting finshed the plumber would install the toilet and fit off the mixer, basin etc. And after that you may need fix up the ceiling and replace the fan.
So it would take about 2 weeks to complete the job.
As the budget goes - you should have a minimum and maximum. I'd suggest 7-9k for the labour part (depending on what you do). Then you have the products and materials.
The tiles you would need: 15 sqm for the full wall tiling and 2.5 sqm for the floor.
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