Do check whether the group has an engine fund or other reserves. Many don't, but will expect that members will put up any necessary funds as required.
As a 1/5th or 1/10th owner, you will be expectyed to make up any shortfalls as they occur
For example, although it is assumed that an engine might last 2000 hours or so, it may fail at 1000 hours. You will need to put up monies to repair the engine at half the planned life, so never assume the reserves will cover the bills.
Too many share-holders find that they will need to find serious amounts of cash even though the group may have reserves. In my group, recently formed, we have not much in the way of reserves, but accept the risk, in the short term.