are you able to sell just the hardtop to a miata vs. selling the car?
yes, providing that you want to.
Of course - I believe it was an option, so it's not expected to be with the car. If you plan on selling it at any time in the future, you may want to keep it, because it's a nice selling point. Search eBay to see what you can expect to get for it, if you do decide to sell. On both my Miata and my S2000, the hardtop has spent more time in the garage than on the car, but it's always nice to know I can put it on for really bad weather. You may want to keep it, for the same reason.
I have kept my current hard top, but on previous cars I sold the top separately...worth $700!! Very good audience for them and you get more in cash than you will selling it with the car or trading in at a dealer. I sold one miata without the hard top, but gave the buyer the chyoice...was only going to charge them $450-500 and then sold it for $700 in a week or two.
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