Sorry if this sounds stupid, but what kind of regular maintainable?
In the 159 all I have to do is put fuel in and go. Lol
Oil and filter change once a year or every 10,000 miles, which ever is sooner, using a good quality fully synthetic oil 10W60 grade.
Air filter at least every two years....I replace mine annually as it's only £20.
Pollen filter every year.
Full belts, pulleys, tensioners and water pump change every 3-5 years depending on your preference.
Keeping on top of general issues and sorting them out before they become a problem. Some cars let you drive on and on with a fault and they never go wrong.....Alfa's take a dislike to this....ignore any obvious faults at your own risk.
Generally the V6's are very reliable, but you do need to keep an eye on coolant and oil levels, and make sure that the full belt change isn't skimped on. Like any older car he suspension bushes/ball joints will wear over time, but once renewed will last for a long time.
Rear tyre wear on the inside shoulder can be an issue because of the camber set up, but it pays you back with a nice handling rear end.
Basically don't buy one if you expect to be able to just drive it and never pay it any attention.....mundane cars will get you by with such an attitude, but mini super cars wont