I dont seem to be able to buy any new homes, anyone have any idea what is wrong?

To buy new homes, you need:
- enough money to cover the initial cost (e,g, $500 for shared apartments)
- enough free time to deal with extra chores (e.g. shared apartment has 60 minutes of chores every day, while basement has 30 minutes, so the game won't let you switch unless you have at least 30 minutes of free time)

There's also the ongoing cost, e.g. 25$/day for the shared apartment, though that shouldn't be the issue here, as the game would let you upgrade even if that would put you on negative net income, so long as your balance is positive. So I expect it's probably the free time issue.