I owned a kit car years back, had the same problem. Ended up just carrying liability. That maybe your only choice.… Yes, I tried both Hagerty and Grundy (I have had Haggerty for years on my 1969 F100 pickup), but they both say they won’t cover a Smart even though it’s a generation one. Just yesterday, a gentleman at Smart Madness told me they used Hagerty in the past to insure their 450 Smarts! I called Hagerty back, and still no dice!
There may not be enough value left on the car for insurance companies to write a collision & comprehensive policy on. Just staying.