Monocock
"200 hours a year equates to 35 minutes flying every day. If that was required to justify a/c ownership I don't believe anybody would buy an a/c. (I certainly wouldn't have done)."
I believe I addressed this in the post of mine to which you responded. I did say that there are benefits in ownership which you can't put a value on.
The 200 hours figure is of course approximate. You can "operate" (the kindest word I can think of) an old piece of junk more cheaply, if you don't mind flying an old piece of junk in which just enough stuff works to make it daylight-VFR legal.
If you run a plane on a Private CofA and do your own maintenance (with no valuation of your own time), and it is a 1970 C150, the operating cost will be a lot lower than if you fly a really nice IFR-capable plane. Perhaps you could achieve a breakeven at say 100 hours (compared with self fly hire).
In this forum, some people here do fly old and very basic planes while others don't, but many questions of this type cannot be answered unless the proposed activity is known in some more detail.
Let's put some figures on it at one end of the spectrum:
A £200k plane on a Public CofA, still within warranty, and ignoring interest on capital:
Fixed costs:
insurance 4k,
hangarage 4k,
annual 1k.
Misc crap 1k.
So your annual fixed costs are 10k a year.
Variable per-hour costs:
£40 juice
£15 engine fund
£3 prop fund
£8 50-hr service
£10 150-hr service
So your hourly cost is £75/hour - actually very cheap considering it would cost you at least £250/hour to rent such a plane, even if you could find one, which is doubtful.
Now, at the other end of the spectrum. I have never oned one of these but I know of some figures, e.g. a 1970 C152 on a Private CofA and self-servicing:
Fixed costs:
insurance 2k,
hangarage zero, parking on grass £1500
annual 1k.
Misc crap 1k.
So your annual fixed costs are 5.5k a year. Obviously there are airfields where parking is cheaper, and insurance is not mandatory!!
Variable per-hour costs:
£25 juice
£10 engine fund
So your hourly cost is £35/hour, and if you can rent one for say £80/hour then the breakeven point is about 120 hours, and less if parking is free and you don't bother to insure it.
BUT - parking outdoors will rot your plane faster and will rot your avionics damn fast. On a well equipped plane this can make hangarage cheap at twice the price, quite literally. You can get some serious maintenance suprises.
As regards how much is spent checking a plane out before purchase, well as with a car you could be lucky. But most used cars are pretty good these days. With a plane you could easily buy a can of worms. I have looked at a fair few used planes and it is apparent that there is a lot of junk on the market.
Just a few thoughts...