Some would say that Joe Average is not meant to be able to afford a Ferrari, but I think that's both unfair and wrong.
In my humble opinion - they need not be prohibitively expensive.
If you bought the best 308 GT4 you could find - you're not going to spend a fortune on the purchase, and it should be very reliable.
But - don't go for anything without a scrupulous service history, and don't ruin it's service history. Also don't even consider a 12 cylinder - e.g. 400i - irrespective of how cheap it is to buy.
A good ferrari specialist will usually be cheaper than an offical dealer for servicing/maintenance, and shouldn't be looked upon unfavourably at resale time.
Also - bear the following in mind (even though everyone else will think I'm mad!!) the only thing that is recorded against the service history is the services themselves, which must, therefore, be done by the right place. Any other maintenance work you can theoretically get done somewhere else. Of course you always want to make sure that you've got a top notch mechanic working on the car. But there are a lot of very good mechanics out there who usually work on other models, and who as a result will be cheaper to use. They're also often the people who will give your car the most careful attention - largely because it's a Ferrari, and they enjoy working on them as much as you enjoy owning them.
Finally - the thing that'll probably worry you more than anything is the engine going bang one day - as if it happens, it's going to cost you BIG TIME! But if you're prone to worrying about that sort of thing, I'd suggest you stay in bed!!
Bazil