Item 2. Properties

At December 31, 2020, we had controlling ownership interests in 2,548 self-storage facilities located in 38 states within the U.S.:

(a)See Schedule III: Real Estate and Accumulated Depreciation in the Company’s 2020 financials, for a summary of land, building, accumulated depreciation, square footage, and number of properties by market.

At December 31, 2020, 27 of our facilities with a net book value of $102 million were encumbered by an aggregate of $25 million in mortgage notes payable.

The configuration of self-storage facilities has evolved over time. The oldest facilities are comprised generally of multiple single-story buildings, and have on average approximately 500 primarily “drive up” spaces per facility, and a small rental office. The most prevalent recently constructed facilities have higher density footprints with large, multi-story buildings with climate control and 1,000 or more self-storage spaces, a more imposing and visible retail presence, and a prominent and large rental office designed to appeal to customers as an attractive and retail-focused “store.” Our self-storage portfolio includes facilities with characteristics of the oldest facilities, characteristics of the most recently constructed facilities, and those with characteristics of both older and recently

constructed facilities. Most spaces have between 25 and 400 square feet and an interior height of approximately eight to 12 feet.