Miata: One Year Cost of Ownership
I'm actually late on this one, since I've now had the car for 16 months or so. Other than the modifications I've already detailed (here and here), the only out-of-pocket costs have been gas and the 5,000 mile service ($106). Oh, and I also applied protective film to the front of the car right after purchase to protect the paint from chipping. That was pretty pricey (~$2k), but it's a one time cost.
Overall, that sounds pretty great, especially when compared to the maintenance costs I had with my previous cars. But you expect low maintenance costs for a new car. The trade-off is depreciation. And there, the news is never good for a new car. Kelley Blue Book estimates depreciation of about ~$5k from my purchase price (that's not counting taxes, title, and registration costs, which in California are another 10% or so on top of the purchase price).
This still makes the Miata the cheapest to own of the cars I've discussed on this blog (but not as cheap as my 10 year old Honda Fit). Of course, as time goes on, depreciation will slow, but maintenance costs will rise. Well, at least a little. Maybe. (My 1997 Miata required basically nothing other than gas and oil changes.)
Here's hoping that the cost of ownership will continue to be far less than the 2002 Porsche or 1965 Corvette.