Mines got 121,000 miles and it's sweet.........Can't say about insurance in your case,you don't say where you are.....As for where I am insurance companies rip us off.Although cars 15 years or older can be classed as classic.
It all depends on a number of factors. For example, I'm a bit of a stickler on PM. I have a binder with every service done and every invoice on my car, along with the PO dealers VMI printout. I change the oil and filter every 5K miles (cheap insurance and I watch the sales ads). Air filters every 10K. I only use OEM parts. I've just had the second tranny service at 110k miles.
I bought an extended warranty with the car and have maximized it's use. I heed the advice of other knowledgeable forum members (e.g., fabbris1, gregs210, and others). I really don't see it requiring any extra work than other high performance cars. And it runs like a champ.
So look for one that has as much documentation as possible.
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