converting rental to primary home, no intention to sell

Hello, We're in the process of purchasing a single family house that my wife and I imagine ourselves living in a few years from now.  Looking through posts, everything I have seen deals with the tax implications of converting a rental to primary and then selling two years later.  I'm not interested in selling and am looking for advice on what we can do that would be advantageous before becoming our primary home.  For example----

1) The loan can be refinanced from an investment to primary, assuming interest stays this low.

2) All the repair and renovation work we do in the next few years will count as a business expense.

Is there anything else that can be done to offer a financial benefit?

Its likely we would also build a basement apartment and rent that out if we live in the main part of the house.