That's ok, they can promise more with no intention of ever paying it because there's a special privileged 'preferred' stock that the bigger investors and executives get that's prioritized for sales and dividends before anyone else's.

You are not kidding. I have some experience with startup stock options and... it's not pretty.

Before anyone retorts with remarks about "phantom stock" and other similar offers, I want you to do some math.

Figure out what the 'strike price' of that stock is likely to be when it matures, and calculate what the payout will be. Then figure out capital gains tax and subtract that. Divide what's left over by the amount of unpaid overtime (hours in excess of 40 a week) you're going to put in for the maturation window. Lastly, compare these figures to other testimonials in your field, and also, look up typical yearly bonus figures for more mature companies. You're going to see that it's not a lot of cash for the extra time, that it's nowhere near your base pay rate, and more established companies are going to do a better job of compensating folks for less effort. You may even find that with a 996 grind-set, it might pay out less than taking a second job at retail.

I can also warn you that if the company sells instead of going IPO, you may get a much smaller payout than all that. I was in a situation where they threw the advertised strike price in the trash, and negotiated a sale of everyone's stock to the buying company for much, much less.