I have used about every type of incubator up to about the $600 range. Still air will work, but has cooler/hotter spots in chamber. Ideally you want forced air...but they cost a little more. You don't have to have an egg turner, they are nice, but cost more. When NOT using one, take pencil, not pen and mark X on one side of egg. Turn egg either X up or X down each day, keep them all the same for that day. So each day will be all X's or no X's.

Grow out time depends on how big you want them. Usually a couple months for me. But I have a big apetite and eat just about everything out there.

Quail feather within in a week. I keep mine inside for 1 week. 2nd week they are outside during day and in at night. 3rd week they are outside, sink or swim. But I give them a 60 watt heat lamp about 14 inches off the ground from sundown to sun up. They survive by forming coveys to stay warm.

So as long as you have say 10 birds, your fine they will keep each other warm once they are feathered.
Look into a "lock down" period. This is key with any incubating. Don't assist hatches. It's tempting but you will learn there's a reason they are struggling hatching. IF they survive, the ones you helped out are never quite right and usually are defective. Quail tempts and time to incubate are different than chickens. Research BEFORE starting a set to prevent issues. Do NOT wash eggs you tend to hatch. The water plugs the pores in shell and suffocates developing embrio. The ones that don't hatch, open and observe what went wrong? Bacteria? Deformed ( usually caused by not turning enough or too much-embrio settles to one side and dies) where they shrink wrapped? I could write a whole website just on trouble shooting hatches.

Bottom line....you will learn. And they lay enough eggs, that you will run out of incubator space before long. Research it.....do it....when you fail, and you will at least once, we all do. Open the eggs in a well ventilated area and find out why. What you find when you GENTLY open the egg identifies the problem.

Always always always give them 2-3 days LONGER than the calendar says. Nature is sometimes a little off. And IF your temp fluctuated, or humidity was off it WILL effect the hatch rate, days to hatch, AND gender...the last one is debated frequently. I am going by 30 years of first hand experience with this. I will always take my first hand experience over a book, some bean counter in a basement with no windows wrote. Also, I did game birds and poultry in 4H as a kid, amongst other projects.

On the incubators....still air works, just not as consistent. I have even hatched reptiles in still air ones. They are just a pain. And for just a little more money there are far better buys out there. IF this is something that you are going to do....I would encourage the proper tool for the proper job.
IF you are unsure, go still air till you decide as small investment if you change your mind, and people readily buy them on CList.