Daily412, I have put a few commetns together in CAPS after the questions.
1. Parts are expensive/impossible to find? YES, AT THIS POINT SOME PARTS ARE HARD AND EXPENSIVE TO SOURCE
2. The engine is weak, breaks often? NO, THE ENGINE IS VERY SOLID
3. Simply the 12 cylinders are 50% more than 8? TO A CERTAIN EXTENT, YES.
4. Packaging, is it necessary to take the motor out for many repairs? NOT REALLY.
5. Requires a lot of special expensive tools NO MORE SO THAN ANY OTHER FERRARI
Changing oil, plugs, cam-chain doesn't sound very complex, butmaybe it is? What I fear most is the injection, I've had no experience of that. THE INJECTION SYSTEM IS LESS HASSLE THAN THE EARLIER WEBER CARBS
THE BIGGEST ISSUE WITH THE 365/400/412'S IS RUST. THEY SEEM VERY EXPENSIVE TO RUN BECAUSE OF THE LOW PURCHASE PRICE BUT REALLY ARE NO MORE EXPENSIVE THAN OTHER 12 CYLINDER 2+2 LIKE A 365 GTC/4 OR A 456 GT.