They don't, and that's why I said they micromanage their kids.
If Anna doesn't meet the income guidelines to rent, she'll find out when she submits an application. Neither Trent nor Amber need to say a thing - and they shouldn't.
Amber said something in one of the THs about Jonah, Elizabeth, and Anna not knowing how to do adulting (paraphrasing), and that may be true. But they won't learn how to do it right unless both Trent and Amber step aside and let them learn - not from their parents telling them what to do and how to do it, but through their own life experiences.