I rent out a single condo as an investment, not a business. I recently replaced some appliances in the unit and I'm wondering whether I can use the de minimis safe harbor for tangible property.

In IRS Pub. 527 (Residential Rental Property), under the section for the de minimis safe harbor for tangible property, they refer to IRS Pub. 535 (Business Expenses) for details. Since I am not operating as a business, can I still use it?