The way Niantic defines “private property” is only if it is SFPRP - single family private residential property. You can see a clarification here Private Residences, Farmland & K-12, or by tapping on the tool tip in the review flow:
I don’t see how a random bench would meet any of the eligibility requirements (Wayspot Criteria — Wayfarer Help Center) but the shutter art may if this is a business location and not a family home.