Expansion is a Cash purchase at your base, not a building minigame. Official order puts income upgrades first, then expand your base to hold even more animals.
You need it when a new animal has nowhere to stand. One house got full on the spot after a hatch. An unplaced animal is not earning.
- Keep animals placed so Cash accumulates, including offline.
- Buy income upgrades so the price is realistic.
- Save at least 1,000,000 Cash for the first tier that was shown. One player saw 1 million required and 7,000 in hand.
- Buy the house upgrade at the base. The exact prompt is not documented. It completed as soon as it was paid.
- Confirm by placing another animal immediately.
It is not confirmed that the base must be full before the button works. In the recording it was full, which may only be when the player looked.
No slot count is published. After paying, the player could place a lot and still said they could not place that many things. Capacity grows and stays finite. The same player was soon saving 5,000,000 for a treadmill, so capacity and Speed compete.
The buy repeats. Later in the session the base filled again. Each time: earn, pay, place. New room pays only after animals are standing in it.