I've also seen a few converted to Taxis.
Those guys do their homework before using any car as a Taxi. So they must be viable.
Most of our Taxis are full sized sedans running on LPG to save fuel costs. It's about half the price of gasoline.
Long term who knows? I've always been concerned about the battery life and replacement costs.
Toyota claims a 9 years battery life. Probably more like 6 years in the real world.
How much does it cost to swap them out?
Most of them would probably be at end of life after 9 years anyways...
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In a word... Marketing.
