I bought a 2000 Boxster S in Dec 2012 with 103,000 miles on it. The previous owner had had the car for the last 6 or 7 years and did not skimp on maintenance. Most of the little stuff that goes wrong with these cars had already happened: AOS, front motor mount, ignition switch, window regulators, MAF, coolant bottle, etc... The PO had also put in a new clutch at around 90 something thousand miles. He didn't do any of his own work, and from looking at the service records it cost him a small fortune.
Since I got the car in Dec 2012 I have done the following:
IMS retrofit with the duel row ceramic bearing - $1350
2 new rear tires - ~$250
(I don't count these first two because this was factored into the purchase price)
Jan 2013 - new wipers - $25, no smoking tray added to center console $30
August 2013 - oil change, Castrol 5W40, Magnetic drain plug $60 (got sweet deal on oil)
September 2013 - Replaced cabin air filter and engine air filter $30
September 2013 - Brake fluid flush $15
September 2013 - Installed litronics $1,000
September 2013 - New ignition switch and headlamp switch $110
October 2013 - Dropped oil filter and replaced to resolve oil overfill $10
October 2013 - Replaced windscreen slips with new design $5
January 2014 - Changed MT Oil $90, Fuel filter $20, Front rotors $100, Spark plugs, tubes and O-rings, $50, o2 sensor, $75
January 2014 - Front hood shocks $20
April 2014 - Replaced front hood cable - parts $15, swaging tools $75. Rear brake/transmission scoops $20, Front GT3 brake deflectors $20
May 2014 - Oil change, $110, KN Spin on Adapter $75, installed EBS Oil Baffle $175, new tires Hankook RS3 $800 with installation
May 2014 - Break down on way to Sebring, tow $360, replace crank sensor $500 (part $140, the rest markup and labor from shop, did not do myself because towing company would bring me all the way home as it was too far)
Around $5,000? Take away the Litronics, $4,000, take away the new tires, $3,300? Take away the IMS (since,I kind of count that as purchase price), brings me down to $2,000 and if I could have gotten the car home and changed out the crank sensor myself that brings me down to around $1700.
Some of it is upgrades (New headlights, non smokers tray, GT3 brake coolers), some maintenance (oil changes, transmission oil change, spark plugs) and some due to failures (crank sensor, headlamp switch, ignition switch). I could have gotten farther on my existing tires but I wanted to upgrade.
For calendar year 2013 my cost was $1395 covering ~7k miles and most of that was litronics. The big service I did January 2014 was only $330. To date in 2014 covering ~1k miles my costs are $2365 and the bulk of that is new tires, and my breakdown (towing and the new crank sensor).
I have probably bought around $500 worth of tools in this time period as well, floor jack, stands, brake bleeder, and other various tools, torque wrenches etc...
If I hadn't done the work myself it would have been hundreds more in labor (thousands? at least hundreds for sure
) and my parts cost would have been much higher as well (witness the $500 for changing a $140 crank sensor, the parts cost for that bill was $250, a significant markup, and the labor part was $250) once you figure diagnostic time to figure the problem, and account for warranty etc) Edit: I am jus tre-reading your original thread, it sounds like you would do most of the work yourself. Big savings there.
This is kind of a long post, and if you search you will see other threads about maintenance costs and the various breakdowns (both vehicle breakdowns, and breakdowns of costs). I think the $2,000 per year is probably pretty accurate.