Where are all the other Units?

The other 900,000 will just hang out in the treasury. If you own 100% of the issued units, then you own 100% of the company. If you’ve set up a multiple member LLC, then maybe there will be 800,000 in the treasury, maybe 700,000. It doesn’t matter how many extra Units there are authorized. It’s only the issued Units that count - i.e. the ones that are actually “sold” to the founders.