I've owned several planes in partnerships. I think the key to a good partnership, is a good agreement IN WRITING. This is probably even more important if close friends are involved.
Although my EZ is not in a partnership (I'm to closely attached to it, as I built it). I would certianly consider a partnership if I were planning on purchasing one. A good written agreement would decide ahead of time, responsibilities, use, whose turn it is, etc.
I've only had one occation were I wanted to fly, and the plane wasn't available (wasn't my week anyway). And only one incident were we had to break out the written agreement, to determine if the partnership was responsible for the cost of retrieving a stranded airplane. (The Agreement said the plane was to be maintained as VFR. The Stranding was related to a VOR that didn't meet IFR specification, The person who stranded the plane was responsible to retrieve it.)
Verbal agreements are as good as the paper they're written on! I'll see if I can find a copy of the agreement and post it on my web site (
www.iflyez.com)
Waiter