I think you're confusing two separate issues.
The first issue is whether your aircraft is a CofA (Certificate of Airworthiness) or PFA aircraft. NotAnother's description of the difference is spot on.
PFA aircraft are
generally cheaper to run than CofA aircraft, for a number of reasons. One reason is that you can do most of the maintenance yourself (just get it signed off by an inspector when you're done - cheaper than getting everything done by a registered maintenance shop). Also, many new home-built aircraft - including my Europa - use fairly innovative designs which use much less fuel than the tried-and-tested CofA aircraft. The cost involved in getting these designs certified by the CAA usually means that by the time you see them in production aircraft (if at all) they are no longer new nor innovative.
Next, you've got the issue of whether to own an aircraft outright, or share it with a group. The main advantages and disadvantages of each are fairly obvious. You can wholly own or part own either a CofA or a PFA aircraft, and that's the point I think you've become confused on. The only exception is that you'd probably find it hard to find someone to sell you a new homebuilt aircraft outright - once someone's built an aircraft, they generally like to fly it. But I'm sure there are exceptions that will prove this rule. Besides which, you can always build your own aircraft if you want to own a PFA aircraft outright! (Uh oh, I've just given Holloway another idea - expect a thread on how to build your own aircraft!
)
As for the mechanics how groups work, well, that's up to the groups to decide. My group uses an internet booking system, and operates on a first-come first-served basis. There are a couple of rules - you can't book more than 1 month in advance, and you can't book for more than 3 consecutive days, without consulting other members of the group. And if the opinion of the group was that someone was hogging the aircraft, we'd have a quiet word with them. Other groups operate differently. But we've never had any problems yet. I'm quite fortunate in that half of my group work during the week and prefer to fly at weekends, whereas the other half either work shifts or are retired, and prefer to fly during the week.
There are two ways of buying a share. One is to get together with a group of like-minded people and buy an aircraft between you. Another is to wait until someone who has a share in his aircraft decides he doesn't want it any more, and is ready to sell it. The latter tends to be easier, for obvious reasons, but you'll be the newcomer in the group and will have no say in the running of the group, you'll have to go along with the rules the group will already have in place.
Hope that answers some of the questions, but NotAnother is right - you have no idea at this stage what kind of flying you're going to enjoy, so it really is too early to be thinking in this much detail about what aircraft you might like to buy.
FFF
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