I’ve been sharing two aircraft:
- a DA40 for 8 years
- a TBM for 5 years
Even though the co-owner was the same, the experience was different. We were flying the DA40 much less. I think 566 hours between us both in 8 years. There was never a problem with access to the aircraft. Then the TBM brought in real utility to move ourselves and families around and we started planning trips most weekends and holidays. This brought the need for some rules. Like this year I take Xmas and you take Easter. Next year we swap. It ended with my co-owner getting an SF50 and me taking over the TBM. So, yeah, sharing can be nice, but you better know your partner well! I would def. not enter with an unknown person and it would be best if the co-owner is busy with a demanding job :)
There are different ways this can be done. A straight out shared ownership is the simplest. Then you can create a club. The club is a legal entity and it will own the plane. A club is run like a small business. There are some advantages with this regarding VAT and stuff, but also training, insurance. But to get the capital for a good plane without the club having any other assets to start with is a process, usually it will involve the club lending money from the members somehow. There are other ways also, an ordinary company of some kind. It’s not clear to me what a “syndicate” actually is, it somehow sound more “businessy” than straight out shared ownership, which is the most common form.
All 6-8 owner cases I have seen were a disaster
There are plenty of syndicates of this size at my airfield and they all seem to work fine. However I can see how it could go south if you end up with the wrong members (hence it is super important that new members need to be approved).
Peter wrote:
All 6-8 owner cases I have seen were a disaster.
I’m in two different 5-10 owner groups, one of them for the last 14 years and the other for the last 7. No significant problems in either of them.
In 10 years of shared ownership I learned a lot more about people than aircraft 
Even when I was responsible for one of the aeroplanes, most of the job was basic admin: receive complaint from pilot, triage (immediate/defer/explain/ignore), liaise with maintenance company, report back to club. What I got out of it was negligible: a few contacts, some background knowledge, and a strong sense of how I would do things differently.
I did have some previous experience from actually flying, hanging around the aeroclub scene, plus reading a few type-specific books. This is easy enough to do.
The Oscar for biggest learning curve goes to sole ownership of an aircraft. ‘Best Supporting’ go to Mike Busch and EuroGA. Jujupilote says it all in post 7.
You could look on Planecheck and ask local sellers if they would consider part-ownership. They might be reluctant to sell, and the worst they can do is say no.