I'm not so sure about shares - I've heard great, but also horrific stories about them. Much more of the latter, though. Even when (Ex-) close friends start a fractional ownership it is not so seldom that they end up at court. My impression is also that it is considerably more difficult to sell a share than a complete aircraft.
Maybe fractional ownerships run better in the UK than they do in Germany, but over here it is very difficult to a.) find an existing share which you could join or b.) find buddies with whom you could start an ownership. Therefore the often only option is to c.) seek for an fractional ownership via the internet what appears to me to be the riskiest option.
I'm not saying that you shouldn't go this route, but I recommend to very carefully asses this option. Another thing you might want to take into consideration is if you really need a 182 or if something more economical like a 172 or Warrior wouldn't also fulfil your typical 95% use case!?
I also have to say, that I am currently renting Cessnas and microlight trikes in two different clubs and that I really have enough of renting - it is always difficult to take the planes away for a weekend, I always have to plan weeks in advance, I always have to fly daily minimum hours and I quite often notice that something is broken during pre-flight.
No matter if it makes "sense" to own from the financial point of view - as soon as I find the aircraft which am looking for, I'm going to purchase it. Alone. Without any partners.
What I might however consider is to rent it to pilots who I personally know.
Cheers,
Oliver