Business Retirement plans and deductions

[James H.]

Hello. My fiance has a house in her name that she would like to rent out in the near future. I've read about transferring to an LLC but most of the conversations deal with liability and not tax, which is my primary concern in asking this question. If she keeps the house in her name and doesn't have a business entity owning the property, are any tax deductions or business benefits not available therefore? For instance, improving your live-in home, if I understand correctly, ads to the cost basis of the property but isn't a deduction. However, it would be a deduction for a rental property owned by a business. But since the house is still in her name, is there any issue with declaring that the improvements are business related? We've made improvements to the house since we lived here as private residents, so would any of those count as business deductions retroactively? In general, are any tax benefits lost if a property is in her name personally?

Separately, does rental income count as a type of income that can be used for SEP IRA or Individual 401K retirement plan contributions?

And final question, since I am also a contractor on the side, if I do any improvements to the property should I not be paid or should I take a reported income. Just thinking through the best approach from a tax perspective for both her and I.

Thanks