We had outstanding service from smith and smith kitchens and are very happy with the quality of the cabinetry. Price was in line with the quality and level of hassle free service. (I started with a good guys quote but opted for 2pac cabinetry and a friend's referral)

as you've been so happy with this cabinet why not invest in a custom made copy that any cabinet maker could reproduce to exactly fit the space and add extra doors or shelves and stronger hinges for the drop down shelf ...check out kitchen and bathroom makers in your local area ...may cost more but could be made to suit your exact storage needs (eg taller unit with more storage, drawers, vertical division to slot in the plastic boxes like small drawers for makeup and glass shelves that are not stained by toiletries and soap ...a cabinet maker could also repair the existing cabinet

A vanity bench can be made to any size. You can still have your storage at 1.5-1.6 metres, but have a bench top running the full length of wall as drawn. The builder is able to install anything that you require which is drawn on your plans and in your budget. Why is the designer saying they cannot provide a long vanity? Is this not in your contract monetary allowance? With a bench top of 1.5-1.6 metres, two basins will be squashed, and would leave no room for bench space. You have two options, either only have one basin installed, or once the home is built, put a freestanding drawer unit which is a similar height to your vanity, along the same wall.

10% for deposit for the planning stage (drawings) 40% once u have signed off so they can get the materials 45% on delivery and 5% on completion this is taking into account they are delivering and plumb, electric, install, tile too.