Pre-built shed to replace old Coop?

[CascadiaRiver]

I live in the rainy PNW and our 16+ year old large shed is finally getting reclaimed by mother nature (water damage, neighbor damage, wear & tear, plus old design & things we'd change now that we know better lol). We also have an old tool shed that I would like to replace with one of those small plastic-y sheds they sell at most hardware stores for under $800 - freeing up a nice spot in our backyard for a new coop!

I have seen ones called chicken coops and ones just smaller sheds- any differences we should note? I may not be able to make my own building but I am capable of making nest boxes and roosts so that's not a huge factor for me, a window is non-negotiable. They seem to come with vents and it wouldn't be too hard to install one or two more, all have a door, I ASSUME we'd be able to get insulation and put it behind some plywood, filling out the walls to extra protect for weather.

They're around similar price, similar size, am I missing anything important?

Flooring: do we try something like loose litter like we have been, or a good time to switch to a new system? I am conflicted here, current old coop has a plywood floor that we do deep litter on and there hasn't been issues but I am unsure if we've just been lucky!

 

[rosemarythyme]

Really no need for insulation in our climate. And if you are satisfied with how your litter has been working for you, I wouldn't see a reason to change.

If your options are the 2 units shown above, obviously the gray one is more set up for chickens with the nest boxes and the larger roof overhang over the windows, but as you are aware even that needs more ventilation as the windows are not sufficient, and the roosts may need to be redone, the nest box door modified to keep water out, etc.

The brown one would need a lot more ventilation but doesn't have much roof overhang, so you'd need to think about how you want to address that. Otherwise a "big empty box" isn't a bad choice if you're willing to add the roosts, nests and vents yourself, as you can set it up to your liking.

 

[Not-so Slick Chicken]

I guess it depends on what your needs are.
Just a few hens?
Mice, mites, predators?

I personally prefer the idea of a store-bought shed over a (local, overpriced) pre-built coop.
Maybe you could even find a clean, used shed for sale at a low price. But not terribly likely, unfortunately.