Well, from a novice's viewpoint, quail seem to be easy to raise--so far. They eat gamebird feed-protein must be higher than 20%. There is game bird layer crumbles too. I am not feeding that right now.
Housing for quail--for me was easy. I used old laying hen cages, and made some alterations.
My first batch of eggs are in the incubator (another expense for raising quail, as they do not sit on their own eggs), so once they hatch, I can report back on whether or not they are still easy to raise.
They are mature (ready to butcher or mate) at 6 weeks of age. Dressed weight of quail is about 4-6 oz, if you are raising coturnix quail. jumbo's are larger--maybe up to a lb, but I can't seem to find any jumbo's. coturnix are easy to find.
My eight birds eat less than a cup of gamebird feed per day. they will lay eggs march through september, unless you give them artificial lighting. Cold does not affect laying. they are cute, make a nice cooing sound, and the males have a very pretty crow. so far I am enjoying raising quail.