A floor to ceiling cupboard would work well in this space. As mentioned in the above comment using Mirror on such a large surface in the bathroom could become a hassle to constantly keep clean. However if you do like to look of Mirror I do suggest a dark tinted mirror, as this would go quite nicely with the colour of your tiles and not look to harsh in the bathroom. For the doors a Pocket door system would work quite well! this is where the door is opened and then you can slide it back to be in line with the cabinetry. I would keep the colours of this cabinetry quite plain and stick to the same colour palette of the tiles. Goodluck !

Sounds like a very stressful situation! If there is absolutely no way the builder will allow you to change things (even if they did, I imagine they would ask you to foot the entire bill of pulling the tiles down and replacing all water proofing in addition to new tiles), I can make a few suggestions for improvement. Firstly I would suggest replacing the tiles above the vanity with a white mosaic, a patterned or a textured feature tile/strip. You could also use this same tile to replace the vertical feature in the shower. There are some beautiful shapes and sizes available to choose from. Secondly I would address the grout situation in this way: Floor - dark colour grout & Walls - Light colour grout. Lastly if it does not prove too difficult or expensive, maybe replace the tiles below the vanity with a plain white tile (could be similar size). Good luck and I am sure once you have a lovely mirror up and some crisp white towels, it will look just wonderful.

Hi Sunaina More than happy to offer some ideas if you can do a rough sketch of the existing floor plan with room measurements. Cheers Liz

yes but I think it depends what market you are likely to be seeking in. if it's not family home market but more up market retirees then a glam spacious bathroom will win more plaudits from buyers than a cramped make-do space. I just strongly feel you should design your bathroom so it is a pleasure to use every day not just the one day a year you may want a bath (plus much as I like the style of bathroom Siriuskey has posted they really don't beg out for bathing in). But a vanity space where you can even have your own toothpaste if you like stripey and he likes plain and all stored neatly away so they never have to appear on display together and with a shower you can lift your arms up in is priceless if you ask me.