This mystery has the reveals in all the right places. It may not be perfect - there's an awful lot of set dressing here - but it's way better than the previous mystery I read. At least I didn't figure out who did it. (I figured out a number of other reveals, but not that one.)
Right, the set dressing. If nothing else, you learn - in a lot of detail - what it means to be traumatized to the extent that you cannot face the outside. Real, visceral, terror-inducing agoraphobia. That, in and of itself, is worth the read because it's not a condition many of us are familiar with, or understand what it means to live with and try to fix.
Layered on top of this are classic noir films that our protagonist watches incessantly - set just so in the book in order for you to tie them into the plot as it unfolds. A bit heavy-handed, sure. But also a delight because they're worth the time to enjoy them again in whatever way is presented.
And layered on top of that is a plot that's constantly weaving and shifting. Yes, there are implausibilities - the way-too-mysterious tenant, the cat who gets fed even if nothing else works as it should, heck, the roof scene, for goodness sake - but overall it's a mystery that will keep you wondering, and it's hard to do that effortlessly.