There is a body of opion that if it flies, floats, or (I forget what else, but think it began with f too), it's generally cheaper to rent or share.
Personally I compromise. I have a share in a big syndicate running a PA28 - that costs me roughly half what it would to rent a similar aeroplane, with the huge advantage of being able to take it away for up to 3 days at a time.
For fun, cheap, local flying I own a microlight. That costs me about £500pa whatever I do with it, and adds about another £13/hr in direct operating costs - so around £1k pa for 40ish hours of flying.
Running a high value permit aeroplane, or virtually any CofA aeroplane is fine - if you are flying the sort of hours people like bose-x are. Otherwise join or setup a syndicate, better to join one since other people have made all the mistakes already and you can learn from them.
G