Kefuddle,
1.1 - Depends on the aircraft. It it's a PA28, C172 or similar, probably very high. If it's a single-seat tail-dragger you might need 100 hours of tail-dragger time. Generally, anything that's got more than one seat won't be a problem - you'll just need to get checked out by an instructor, and if it's a more complex aircraft than you're used to, that may take time. Also depends on the group to a small extent, too.
1.2 - Varies from group to group. The group I'm in uses an Internet booking system, first-come first-served. The rules are that you can't book more than a month in advance, and you can't book more than 3 days in a row. Seems to work very well - we have a mix of weekend fliers and weekday fliers which avoids too many conflicts. Other groups may have similar or completely different rules. This would be on thing you'd want to check before buying into a group
1.3 - Not generally, although if you're paranoid about it I'm sure you could set something up..... Personally, I wouldn't want to be in a group if I didn't trust the other members.
Can't help with the questions on ownership, though.
FFF
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