We went through this a couple of years ago. Wife insisted on talking to some of the big companies. On one occasion I walked out of the room while the sales ****t was talking because he was just unbearable. Another argued with me claiming what I wanted couldn’t be done. Until I explained to him how to do it and then he agreed with me.
None of them truly did fitted wardrobes. They had a selection of standard carcasses and would cut blanks to fill any gaps.
In the end we went custom made, a cabinet maker who’d done some work for my brother. Similar price overall but everything was made exactly to our dimensions, exactly to our requirements. Nothing is a standard size. No up front price list, of course, but we were able to give him a budget and he adjusted the spec to suit.
We are very happy with the results.