Cars like the Smart ForTwo are developed by huge companies that have other models to support these projects. And the smart is nearly double the cost of an Elio. Don't get me wrong, an Elio could work, but not at $7k. That's my entire point. There is no way such a niche type car can sell at such a low price without selling volume like a Corolla.
Marketing can only go so far. People know what they want, and marketing can only convince a certain % of people. Marketing isn't going to convince people they can do without the cargo room, safety, practicality, etc. The large majority of car buyers will pass on the Elio regardless of fuel economy simply because it doesn't have 4 doors or 4 seats. Marketing isn't going to convince people to give these things up. Auto makers have gone to extreme lengths to satisfy these demands to sell cars. How can anyone believe Elio can march in a change what people want? Automakers would be selling a 3 wheeled super commuter if that's what people wanted.
Comparing the Elio to something like a Can-Am Spyder is a good discussion. The Can-Am Spyder is not marketed as a commuter car or a daily driver. It's a fun accessory. It's also much more expensive. There is a market for fun toys like sports cars or motorcycles, but if people are going to spend the extra money on an extra car they are going to buy something that is actually fun, like a motorcycle or truck for work or a sports car. Why would anyone buy an Elio as an accessory? It makes a great commuter car, that is for sure. But the amount of people who can afford a regular car + a commuter car is small, and again the Elio needs to sell lots of volume to keep it's $7k price tag, so marketing in that way isn't going to work either.
Elio has made a big mistake by promising a price tag and a MPG number before they are at the production stage.
That is their marketing plan. They have convinced a large number of people they can buy a brand new hyper-fuel efficient car for $7k. That is enough to generate good press and hype, but what happens if Elio cannot meet it's promises?
And the option of marketing it as a fun, lightweight sports machine is futile as well. Even adding a performance engine isn't going to help. There are already better options for thrill seekers and people who want to go fast: