At June 30, 2020 and December 31, 2019, property and equipment, net, and other assets consisted of the following:

	June 30,		December 31,
	2020		2019
	(Unaudited)
Property and equipment, net of accumulated depreciation of $2,095,387 and $1,994,320 as of June 30, 2020 and December 31, 2019, respectively	$	634,461	$	534,465
Right-of-use operating lease asset		1,313,828		1,595,044
Security deposits and other assets		345,599		306,585
Property and equipment, net, and other assets	$	2,293,888	$	2,436,094

We compute depreciation using the straight-line method over the estimated useful lives of the property and equipment. Depreciation expense for the three months ended June 30, 2020 was $50,846, including $14,455 of depreciation expense reflected within “Cost of revenue” in our condensed consolidated statements of operations as it related to assets used in directly servicing customer contracts and was $101,067 for the six months ended June 30, 2020, including $28,273 of depreciation expense reflected within “Cost of revenue.” Depreciation expense for the three months ended June 30, 2019 was $49,112, including $15,511 of depreciation expense reflected within “Cost of revenue,” and was $116,629 for the six months ended June 30, 2019, including $49,009 reflected within “Cost of revenue.”

We recorded a right-of-use operating lease asset related to our corporate office lease upon the adoption of Accounting Standards Codification (“ASC”) 842 effective January 1, 2019. Refer to Note 7, Leases for additional information.

On February 20, 2018 (the “Closing Date”), we entered into an Asset Purchase Agreement with Earth Media Partners, LLC to sell certain assets of our wholly owned subsidiary, Earth911, Inc., in exchange for a 19% interest in Earth Media Partners, LLC, which was recorded as an investment in the amount of $246,585 as of the Closing Date, and a potential future earn-out amount of approximately $350,000. The net assets sold related to the Earth911.com website business and consisted primarily of the website and its content and customers, deferred revenue, and accounts receivable as of the Closing Date. Earth911, Inc. was subsequently renamed Quest Sustainability Services, Inc. The carrying amount of our investment in Earth Media Partners, LLC is included in “Security deposits and other assets” and we have an accrued receivable in the amount of $213,098 related to the earn-out included in “Accounts receivable” as of June 30, 2020.