On the one hand the automatic GTV 2000 is a rare beast - on one forum they were speaking of just 25 automatics being produced - if this is indeed correct, then really
rare! If the car is in mint condition for 11000 euros then it might be worth considering - who can claim to have one of 25 alfas produced? (if that number is correct, that is - I somehow doubt it but who knows). One thing is for sure you will not get a mint bertone GTV for 11k - those days are gone.
On the the other hand lots of spares will simply be unobtanium - consider for instance the radiator, easy to find for a normal gtv but for the automatic it has a built in oil cooler for the auto transmission oil, so too I would think the kickdown cable would be nearly impossible to find. I can imagine there is a whole number of things different on an auto alfa, like consoles, maybe speedo drive, sensors to keep the idle correct when in "drive", propshafts, giubos etc, gearbox mounts, bellhousings etc., etc.....
One positive is, you wont have 2nd gear synchro grind!
If the car is local to you, take it for a testdrive and see how you like it..before we all condemn it for you
EDIT/correction: I see on alfa BB one auto owner from SA says there were 200 autos produced - that sounds more like it - still rare compared to the thousands of manuals.
Other differences in the car are the rear axle (different ratio to manual cars) crossmembers, gearbox tunnel sheet metal, no clutch plate obviously, pedal box (no clutch), hydraulic lines etc.....any thoughts (as i admittedly first had!) therefore of converting to manual would soon end up in a nightmarish money pit and you would end up with "neither fish nor fowl" as they say.