Which prefabricated house provider - prices, experiences?

Saddled stairs may be considered more attractive, but in my opinion, the mortised version is more labor-intensive. Therefore, I am surprised that the higher additional cost (each compared to: concrete?) is quoted for the mortised version. Could this possibly be explained by the fact that the general contractor buys the other version from a different stair builder (or do the versions also differ elsewhere: without risers the construction is different)?

Presumably, you made a typo,

not the mortised but the saddled version had been more expensive according to the offer.

No. That’s exactly why it surprised me: "gestemmt" is actually more elaborate (with otherwise the same construction, meaning both with or both without risers) and logically should be correspondingly more expensive. The guy can also do "aufgesattelt" without being a master craftsman.

Dadoed (with otherwise identical construction, i.e. both with or both without risers) is actually more labor-intensive and logically correspondingly more expensive. The journeyman can also manage the saddle joint without a master.

For us, the saddled variant on his part also demanded a significantly higher price.

Upon inquiry, this was then attributed to the considerable additional effort in material (two massive support beams, which are milled from solid).