For the most part a 99 miata is very reliable, however there are a few of issues to look out for.
The first issue is the #4 thrust bearing issue that affected 99-2001 miatas. With 62k I doubt there would be a problem, but would have it checked for piece of mind.
Next check that the top folds down correctly and that there are no pin holes behind the driver and passenger window. Some tops had weak springs that caused the rear bow on the top not to go down correctly and pinched the fabric when folded. This can be easily corrected with a couple of new springs.
The last issue is coil packs. These have been known to be a problem for some. Although I haven't had a problem with mine, I've read a lot of posts about the problem on miata.net.
I would certainly ask the dealer if there are any service records. As another poster mentioned it is due for a timing belt change. Maybe you can have the dealer throw that in if you decide to buy the car. When you change the timing belt it is also recommened that you change the water pump, since it is easily accessible when you do the timing belt change.
Do a couple of autocrosses with the car and sign up to Mazdamotorsports to take advantage of cheap parts.
Last suggestion is to go over to
www.miata.net and read, ask questions, read, ask questions, read...
Good luck,
Jeff
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GS - 17 Honda Civic Si
STS - 91 Honda Civic Si
S04 - 00 Subaru Impreza 2.5 RS
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