I've had some experience (in a way) with chapbooks like this, as well with something that another commentor mentioned.
I use MS Publisher for this -- you can do any increment of 4 pages (facing pages, back and front). I've done them up to around 40 pages, but that depends on the actual use. When you print it, it will automatically place the printed pages in the proper order (which is different than the linear order of your manuscript). I then have them printed back-to-back. I do the cover in a separate file, since it is often only one sided and of a different color/weight of paper, but that's personal preference. Publisher is relatively easy to use at a basic level -- if you do that and have questions, you can email me and I'll try to help. There's also plenty of help online.
The other thing was the mention of FrameMaker -- if you haven't used it before (and you may, since you do freelance stuff) -- don't try and use it for something like this. It is one of the most robust things out there that I've seen, but there's a really big learning curve, and for this, it wouldn't be worthwhile for you. (if you're comfortable with it, your mileage on this may vary, but I use FM every day and I'm much rather use MS Publisher for something like this.)
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I use MS Publisher for this -- you can do any increment of 4 pages (facing pages, back and front). I've done them up to around 40 pages, but that depends on the actual use. When you print it, it will automatically place the printed pages in the proper order (which is different than the linear order of your manuscript). I then have them printed back-to-back. I do the cover in a separate file, since it is often only one sided and of a different color/weight of paper, but that's personal preference. Publisher is relatively easy to use at a basic level -- if you do that and have questions, you can email me and I'll try to help. There's also plenty of help online.
The other thing was the mention of FrameMaker -- if you haven't used it before (and you may, since you do freelance stuff) -- don't try and use it for something like this. It is one of the most robust things out there that I've seen, but there's a really big learning curve, and for this, it wouldn't be worthwhile for you. (if you're comfortable with it, your mileage on this may vary, but I use FM every day and I'm much rather use MS Publisher for something like this.)
Can't help you with the other questions, though.