I had a 996 for 12 years. It was the first 911 that was reliable enough to be a daily driver. A common problem is the rear main seal leak, which was a design flaw that persisted through to the early run of the 997 series. Oil drops underneath the car gives you plenty of clues and time to fix this. Would cost about $3K CDN at the stealership, probably half that at an independent shop.looking at possibly adding a car to the garage either this year or next, have it narrowed down to either a Porsche 996, because childhood dreams, or E92 M3 because V8.
anyone own either or both and can offer a first hand opinion?
Less common but still prevalent is the intermediate shaft bearing, which wears out prematurely because the 996 has an "integrated dry sump" which doesn't adequately lubricate the bearing at speed or when cornering, so it wears down leading to an oil leak at the IMS seal. Ultimately results in an engine failure very quickly, so you have less time to diagnose. Also around $3K to replace bearing as preventative maintenance (ask the owner for a receipt), otherwise it's $$$$ to rebuild/replace the engine. A new engine will cost more than what you will pay for the car today.
I never had a RMS or IMS problem, but I did have a cracked cylinder less than 20K on the odo, new engine replaced under warranty. Freak problem, not many other 996s reported having this issue. No other major issues besides (expensive) wear and tear items in the 12 years of ownership.
The 996 was not well-loved when it came out. First of the water-cooled 911s, it made the last oil-cooled 993 an instant collectible. A lot of Porsche guys weren't fans of the design as well, the fried egg headlights vs the classic round 911 ones, the slab-sides vs rounded hips of the last generation and the plasticky interior.
Despite the engine leak problems, it was a lot more reliable than any of the oil-cooled 911s before it and it represents excellent value since resale prices are so depressed. Definitely find yourself an independent shop if you run into any problems and never step foot into a dealership unless you want to be bent over the hood.