Had never really considered this as a problem but I do always have difficulty unloading and reloading my dishwasher and thinking about it, one at eye level would be a whole lot more practical!

Actually it shouldn't be too hard. Someone who knows what the are doing will pull out the existing double unit and replace it with a new smaller carcass and put one of the old doors on it. You need to get them out first as they can advise you if they will be able to fit your second cupboard door onto the dishwasher so it is integrated. It probably won't be the right door for integration in which case you could either find out who made the kitchen and if a suitable alternative can still be bought. Alternatively you get a free standing DW. Look for a handyman or a joiner- particularly one who has fitted kitchens.

Hi - received your email about this post ... in short - no - haven't designed one under a sink before - but that's because the space needed for one of these is just over 40cm ( see pic ) and that would only leave about 30cm for bowl and plumbing above it ... with a vessel sink this might be possible - but not sure how practical the vessel sink would be in a kitchen ? If this is an Au pair /granny flat kitchen that is a secondary cooking space - then maybe ok - but if it's a primary cooking space I'd reconsider that kind of sink as it might be a bit awkward. Man about the house might be able to help ? Maybe a shallow shower trap instead of standard trap might help ?

Worktops I agree are fine and usually an upstand or splashback would be fitted to cover any gaps from uneven walls, End panels should not require that much filler when fitted and it looks as if the kitchen level could have been dropped a little and this will also get over the gap under the plinth. I thought the plinth was not only to cover the void under the units but it also provides added support to the base units when loaded up to help spread the weight and really should be fitted with a 5 mm or less gap so they can be removed if needed. pipe outside is not fitted properly as over time this will sag as there are no fixings to the wall to hold it in place, and the fact the appliances won’t fit says to me that the kitchen was not set out correctly from the start or there is a fault in the design. If I were you I would be going back to the company demanding these things are corrected. I hope you get it sorted and can enjoy your new kitchen soon.