Hi havoc!
As i never owned one of these cars,all my informations are sourced from private discussions with fellow members of the HellenicAROC,various Alfa & Fiat owners fora and the press (specially from AutoItalia's tests and buyer's guides).
Starting with the GTV, i will refer only to the 2lit and 3-3,2 lit models,which were oficially imported in Britain.The big V6 us a very reliable,higly developed unit and is regarded by the motor press and alfisti as being the best V6 ever produced,in terms of performance and magnificent sound.Its large capacity and high insurance rating guarantees that 3,0GTV is unlikely to have been used as rep's wheels.It has high fuel costs and belt replacement at the prescribed intervals is essential (every 72.000 miles with charges from 75 to 47 pounds per hour.And an official dealer needs 7 hours for this work)Most 3 lit cars are fitted with a 5 speed gearbox but later cars also offered a 6speed unit.This is irrelevant with such a powerful engine and is a disadvantage in practical use (if you are cruising in 6th and an overtaking opportunity arises then it may be necessary to miss out 5th and select 4th gear to find the power band of the high revving 24valve engine).From reliability point of view 2 lit TS engines suffered from some inconsistency.Heavy oil consumption was an issue that led to premature crankshaft wear and mechanical failure.The new JTS engines have solved any reliability issues according to Alfa Romeo.Cambelt changings should be carried out sooner than later.Seized cambelt tensioners are common, causing the belt to slip and resulting in valve damage.A worn variator,which automatically alters the valve timing, will cause a rattle on cold start-up.This is a common fault.Although alarming the defect doesn't appear to have effect on engine performance or to result in mechanical damage.GTVs are well balanced cars with sophisticated suspension but handling efficiency can be affected by wear.Any incosistency in the steering or creaks and groans from any area should be viewed with suspicion.Any "kangarooing" under low speed running will probably be due to worn engine mountings.Early GTVs with high mileages is not a problem on either version, if a comprehensive service history is provided.Lighter than the 3lit. the 2lit engine thrives on revs and provides a well-balanced,sporting ride with sharp handling.
Gearboxes and transmissions are generally reliable.Wear will be the result of high mileage or abuse.This may manifest itself in the form of notchy 3rd gear synchro or a worn out clutch.
Alloy wheels should be inspected for curbing, which is evidence on how well the car has been treated.
The serious problem with 3lit. car is the alarming wear rate on the front brakes.With such a nose heavy powerful carthe front discs take a hammering and unless the driver balances his braking with use of the gearbox, the discs sooner or later will warp and judder.Everybody suggests after market products,which are more adequate than the originals and sometimes cheaper.Rear suspension's set up is sensitive to worn dampersand bushes.Any incosistency in steering will be probably be caused by worn or split bushes in the front suspension lower wishbones.
Elecric faults (not very common) will probably have been rectified when the car was new.The fuse box that carries a multitude of fuses should be checked in order to be sure that fuse ratings are correct according to the handboook.
No rust problems.Bonnets are plastic and can fade at a different rate to the steel body panels.Dark colours often show up body defects.
Attention to the keys.A full set of keys , including the code key, should accompany a clean and goodlooking car.If not ,any subsequent ECU fault may prove difficult to rectify.
Although i love GTV's shape and Arese's V6 engine, i would go for the 20V turbo Fiat Coupe.It's four seater with big boot,has greater performance, and is cheaper than the GTV and in my opinion is the classic performance car of the future.
Hope that helps you.As i noticed that you intend to cover 90 miles per day, wouldn't be clever to add to your list a 1,9 16V multijet engined car?Be it 147 or GT?GTV and Fiat coupe are great cars but they are also serious oil burners.Good luck.