You can of course. There's a risk the the stock will move quickly through your limit and you stop out somewhere beyond it. This is unbounded in a sense but not generally problematic on a highly traded stock like Tesla.

That's basically how a margin call works. If your position loses too much money relative to the other components of your portfolio, your broker forcibly closes your position to prevent further losses.

the limit is a trigger for sale, not a guaranteed price. for small volumes (retail) transactions, it usually doesnt matter, but if you are talking hundreds of millions of dollars worth of shares, your activity aloe will move the price.