We are currently struggling with the assembly of the handleless "Metod"
The "Metod" carcass doesn’t differ in being handleless, right? It’s just a different front, namely handleless.
But: it is indeed a struggle.
It’s work and you have to put effort into it... hence the price difference
"Overall construction manual"
There is never one, since the kitchen is a creation made up of arbitrarily combined individual parts. You have to take your time on site, ask questions, observe, and depending on your own capabilities, have some steps done for you. You alone bear the responsibility, which can be both a curse and a blessing. I prefer it that way. Compared to other furniture stores, I have experienced friendlier and more helpful employees at IKEA in various locations, and the people in the kitchen department always had maximum knowledge about their products. Therefore, I cannot confirm your assessment but understand that it can be annoying in individual cases... but where isn’t it. And... you have to be motivated for such a self-responsible project. We were very often there and tinkered and did things. I wouldn’t want to do it alone on the PC.
Thanks for the tip Tolentino, Pagoni! Strange though that they are designed for "fridge/freezers".... At the same time, corner assembly is apparently not possible with them. Only the 37 cm ones remain for corners..., if they even fit. Honestly, I had completely ruled out IKEA so far..., but now I will at least take a closer look.
You should go on site and ask about such things; over time you learn. I’m sitting in my fancy kitchen right now, but you should be aware that with the lower price, some work and responsibility shifts to the buyer or, as we do it, you find the right handyman who then takes care of the fine adjustment during assembly.