I put in a Shaker kitchen last year and so it was my specialist subject for about 18 months
. In the end we were too pushed for budget even for the lovely Handmade Kitchens. I had a plain Shaker door and oak effect carcase from DIY kitchens, and styled it with shelves, a freestanding larder and painted it all in Little Greene. We also don't have much space and there's no getting away from it, in-frame kitchens don't often make good use of it.
I looked at one place in Leicester that made beautiful bespoke kitchens, they made all their units with veneered board or plywood and were definitely worth the money. OTOH my friend has a lovely looking Devol kitchen but IMO the design is so bad it's toxic - appalling storage, inaccessible sink, no workspace where it's needed and full of dust traps.
I suppose some places just have more overheads than others. I think the worst offenders are the DIY places like Homebase and B&Q, they have such a paltry limited selection of units, and often very cheap carcases when you see on DIY-kitchens or something what the full range is and how inexpensive a very solid kitchen can be.
Also don't underestimate design, I am a designer for work so I was OK working it out and drawing it up, but not everyone is up for doing that.