Ok, so here's my take on this, having owned Tesla stock and short sold it not too long ago.
I bought about $3K worth of the stock at the time, and that's all I really could use to "start" investing in a brokerage fund for play money.
I bought stock at a share of about $220 if memory serves me right. I bought only like, 10 shares.
I did my research and saw that this market was going to go up more. Around $250 share price, I sold it. Even before the new model for the preorders went out, I knew I was short selling it for a minimum profit. Why? Because that was essentially my risk tolerance. I got about 10% return for a first purchase, and that wasn't bad. What happens the next day? A few articles go out on the web, Tesla becomes the hot buy, it jumps to $272. I wasn't feeling stupid, because I knew I won what I could.
Again, fire articles spread across media: Tesla stock drops to $235-240. What saves it? Pre-orders go out, now the stock sits up in the $300's range.
Had I stayed in, I would have made more selling now. But investors are scared about this stock, and I agree with that.
Tesla is building the market, not putting a product in a current one. It wants to become the green energy superpower of the future, and it will be someday. It will be the company that makes the electric car, the charging station, the solar roofs and walls and batteries and everything else after that.
And it will be competing with a lot of already well established major industries, so there will be a war of sorts for that.
What can succeed long term? A lot, and the stock will go up and up and up.
What can make it crash and burn? A smart self driving car killing someone? Sure, that rumor did damage already. But what else? Tesla's overconfidence in investors or customers. Investors if they use Tesla not as a smart choice for stocks but to ride the wave and manipulate the buys and sells. To even surmise that, you would need to look into who has majority shares and who or what is driving the sales.
But more so, the customer base. Tesla wants people to drive electric, and that will fuel the need for charging stations. Places like South Korea are well on the way to expanding that market, and if it was anything like the 90's period of semi-conductors, it will be a market Tesla has to compete with or somehow make allies with. But, does Tesla have enough driving force for such a big change in the world environment? That is something time will tell.
Honest opinion with so many factors at play? If you want long term, buy buy and buy more. I think its too late in the game to get into Tesla right now with how high the shares are, but if you got that kind of money then go for it.
Otherwise, with what you got, go short term but be smart about the season for the stock, do the long term research to aid the short term, and sell when you are comfortable.
I took what I won, and I have about $1000 now in Emerald Health Therapeutics (TBQBF), bought at $1.02. I see the stock going up, and I'm expecting good returns over the next one to two years.