Yes it is very possible to tow smart car behind the cali.
I bought an 09 smart for two at the beginning of the year in the cold weather. My cali was not getting up to temperature when I got to work (6 miles) in the very cold weather. I had to continue passed work for another two miles. Decided it was not doing cali engine any good. Cheaper & easier to replace the engine in the smart.
I purchased an A frame to tow the Smart, although this has it's own problems it works well for me.
The smart is a hoot to drive & sticks to the road like glue. It is 84 bhp variable valve timing turbo 700cc. Not the most comfortable ride, but hey ho.
Like the cali there is a lot of smart forums which have a lot of info just like here.
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