The apartment that the maid who the service had sent over was cleaning every week was well decorated.
The first sight of this sentence makes me think of the word "cram", though the term for such sentences is "embedded ones".
This sentence can be broken into three smaller ones, so it is not so hard to understand. Honestly, I cannot remember seeing such crammed ones outside my grammar books, though embedding itself is nothing but a common device.
It's better not to talk about embedding issues in general; instead, I was wondering, what do you think of the specific topic sentence? Would a native really use it in daily life?
Many many thanks.