If $179 buys all 3 pieces, then i say Yeah! that's a fair price. But you should always bargain for a better price!
The #1 problem I see is with the roosting space. You have to think about how your chickens are going to live. Will they be allowed to free-range for most of the day? Or will they be cooped up and if so, how large will their run be? Most on this site recommend at least 4 s.f. per bird inside the coop and 10 s.f. per bird in a run. I have had as many as 12 birds in 32 s.f. in the coop, but they're run is huge and they have instant access to it (the pop door is always opened) and they are also allowed to free-range when I'm home (which is almost every day). I'm down to 7 now (hawks are a bad thing!) and only plan to keep around 10 at any given point so that they have 3 s.f. on the inside, but my roost space is enough to allow for 13-14 birds (which I would never do - too much poo to clean up!). Maybe I didn't look right, but I don't see a door on the smaller 2 pieces???
You need to allow no less than 8" per bird on the roost for regular chicks and 10" for the bigger girls. My girls tend to roost in groups of 3 to 4 and like to have space between the groups. Since mine don't fight very much, guess it's a good thing they have plenty of space around them.
In the beginning, I would start with the smaller # of chicks and if you think you can add more, that's always easy! Good luck!