Get yourself a share and see how you get on with that first.
UA posts excellent advice, I've owned a few and shares are a good way to start, just make sure it's one you can sell on relatively easily.
If you insist on buying a plane buy something popular, it pays off when it's time to sell.
Permit aircraft are significantly cheaper to run but you wont find many 4 seat ones. The main reason for this is that as A and C says that the costs of having all the relevant certificates to do maintenance on an EASA type is mad expensive, more so the parts which must come with a certificate that costs a bomb.
Ownership is always about 50% more expensive than you expect it to be and you'll use it probably 25% as much as you hope, so be prepared
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