Somewhere between the intersection of car and motorcycle lives the Snyder ST600-C, a Chinese built thing with 3 wheels and 4 seats. It was a revealing peek into the dystopian future, but alas it seems that Synder Vehicles has shut down operations and if you want one, you'll need to get it used. Like this 2011 Snyder ST600-C offered for $1995 in Tacoma, WA. Tip from FuelTruck.
How bad can a 3-wheeler be, you ask? Given the $7995 MSRP when new, you'd think that it couldn't be that bad, but consider that this 4 year old example has only 2700 miles on the odometer and is now offered for less than $2k. This thing drops residual value like an Audi.
Unfortunately, depreciation is the only thing the Snyder shares with an Audi. The interior looks like it was stolen from a Barbie-Jeep and the engine from a riding lawnmower...actually...it probably was taken from a riding mower. A 600cc twin cylinder 4-stroke engine puts out 35 horsepower into a 4-speed manual putting power into the rear wheels. Turn at your own risk.
See a better way to get 60mpg in a 4-seater? firstname.lastname@example.org