Principles of Consolidation. Our condensed consolidated financial statements include our accounts and the accounts of other subsidiaries and joint ventures (including partnerships and limited liability companies) over which we have control. All intercompany transactions, balances, and profits have been eliminated in consolidation. Investments acquired or created are evaluated based on the accounting guidance relating to variable interest entities ("VIEs"), which requires the consolidation of VIEs in which we are considered to be the primary beneficiary. If the investment is determined not to be a VIE, then the investment is evaluated for consolidation primarily using a voting interest model. In determining if we have a controlling financial interest, we consider factors such as ownership interests, decision making authority, kick-out rights and participating rights. As of September 30, 2021, two of our consolidated operating partnerships were VIEs. We are considered the primary beneficiary of both consolidated operating partnerships and therefore consolidate these operating partnerships. As of September 30, 2021, we held approximately 93% and 95% of the outstanding common limited partnership units and the sole 1% general partnership interest in each of these consolidated operating partnerships.

Interim Financial Reporting. We have prepared these unaudited financial statements in accordance with accounting principles generally accepted in the United States of America ("GAAP") for interim financial statements and the applicable rules and regulations of the Securities and Exchange Commission ("SEC"). Accordingly, these statements do not include all information and footnote disclosures required for annual statements. While we believe the disclosures presented are adequate for interim reporting, these interim unaudited financial statements should be read in conjunction with the audited financial statements and notes included in our 2020 Annual Report on Form 10-K.

Acquisitions of Real Estate. Upon an acquisition of real estate, we determine the fair value of tangible and intangible assets, which includes land, buildings (as-if-vacant), furniture and fixtures, the value of in-place leases, including above and below market leases, and acquired liabilities. In estimating these values, we apply methods similar to those used by independent appraisers of income-producing property. Estimates of fair value of acquired debt are based upon interest rates available for the issuance of debt with similar terms and remaining maturities. Depreciation is computed on a straight-line basis over the remaining useful lives of the related tangible assets. The value of in-place leases and above or below market leases is amortized over the estimated average remaining life of leases in place at the time of acquisition; the net carrying value of in-place leases are included in other assets, net and the net carrying value of above or below market leases are included in other liabilities, net in our condensed consolidated balance sheets.

We recognized amortization expense related to in-place leases of approximately $8.4 million and $0.3 million for the three months ended September 30, 2021 and 2020, respectively, and approximately $10.9 million and $9.1 million for the nine months ended September 30, 2021 and 2020, respectively. We recognized revenue related to net below-market leases of $0.2 million for each of the three and nine months ended September 30, 2021 and did not recognize revenue related to above or below-market leases for either the three or nine months ended September 30, 2020. During the three and nine months ended September 30, 2021, the weighted average amortization periods for in-place leases were each approximately ten months, and the weighted average amortization periods for net below-market leases were each approximately ten months. During the three and nine months ended September 30, 2020, the weighted average amortization periods for in-place leases were approximately six months and seven months, respectively.

Asset Impairment. Long-lived assets are reviewed for impairment annually or whenever events or changes in circumstances indicate the carrying amount of an asset may not be recoverable. Impairment may exist if estimated future undiscounted cash flows associated with long-lived assets are not sufficient to recover the carrying value of such assets. We consider projected future undiscounted cash flows, trends, strategic decisions regarding future development plans, and other factors in our assessment of whether impairment conditions exist. While we believe our estimates of future cash flows are

reasonable, different assumptions regarding a number of factors, including market rents, economic conditions, and occupancies, could significantly affect these estimates. When impairment exists, the long-lived asset is adjusted to its fair value. In estimating fair value, management uses appraisals, management estimates, and discounted cash flow calculations which utilize inputs from a marketplace participant's perspective. In addition, we evaluate our equity investments in joint ventures and record an impairment charge if we believe there is an other than temporary decline in market value below the carrying value of our investment. We did not record any impairment charges for the three or nine months ended September 30, 2021 or 2020.

The value of our properties under development depends on market conditions, including estimates of the project start date, projected construction costs, and demand for multifamily communities. We have reviewed market trends and other marketplace information and incorporated this information as well as our current outlook into the assumptions we use in our impairment analyses. Due to the judgment and assumptions applied in the impairment analyses, it is possible actual results could differ substantially from those estimated.

We believe the carrying value of our operating real estate assets, properties under development, and land is currently recoverable. However, if market conditions deteriorate or if changes in our development strategy significantly affect any key assumptions used in our fair value estimates, we may need to take material charges in future periods for impairments related to existing assets. Any such material non-cash charges could have an adverse effect in our consolidated financial position and results of operations.

Cost Capitalization. Real estate assets are carried at cost plus capitalized carrying charges. Carrying charges are primarily interest and real estate taxes which are capitalized as part of properties under development. Capitalized interest is generally based on the weighted average interest rate of our unsecured debt and was approximately $3.5 million and $4.4 million for the three months ended September 30, 2021 and 2020, respectively, and was approximately $12.8 million and $13.0 million for the nine months ended September 30, 2021 and 2020, respectively. Capitalized real estate taxes were approximately $0.2 million and $0.8 million for the three months ended September 30, 2021 and 2020, respectively, and were approximately $2.7 million and $3.7 million for the nine months ended September 30, 2021 and 2020, respectively.

Expenditures directly related to the development and improvement of real estate assets are capitalized at cost as land and buildings and improvements. Indirect development costs, including salaries and benefits and other related costs directly attributable to the development of properties, are also capitalized. We begin capitalizing development, construction, and carrying costs when the development of the future real estate asset is probable and certain activities necessary to prepare the underlying real estate for its intended use have been initiated. All construction and carrying costs are capitalized and reported in the balance sheet as properties under development until the apartment homes are substantially completed. As apartment homes within development properties are substantially completed the total capitalized development cost of each apartment home is transferred from properties under development including land to buildings and improvements.

Fair Value. For financial assets and liabilities recorded at fair value on a recurring or non-recurring basis, fair value is the price we would expect to receive to sell an asset, or pay to transfer a liability, in an orderly transaction with a market participant at the measurement date under current market conditions. In the absence of such data, fair value is estimated using internal information consistent with what market participants would use in a hypothetical transaction.

In determining fair value, observable inputs reflect market data obtained from independent sources while unobservable inputs reflect our market assumptions; preference is given to observable inputs. These two types of inputs create the following fair value hierarchy:

Deferred Compensation Plan Investments. The estimated fair values of investment securities classified as deferred compensation plan investments are based on quoted market prices utilizing public information for the same transactions. Our deferred compensation plan investments are recorded in other assets in our condensed consolidated balance sheets. The inputs associated with the valuation of our recurring deferred compensation plan investments are included in Level 1 of the fair value hierarchy.

Non-Recurring Fair Value Measurements. Certain assets are measured at fair value on a non-recurring basis. These assets are not measured at fair value on an ongoing basis but are subject to fair value adjustments in certain circumstances. These assets primarily include long-lived assets which are recorded at fair value if they are impaired using the fair value methodologies used to measure long-lived assets described above at "Asset Impairment." The inputs associated with the valuation of long-lived assets are generally included in Level 3 of the fair value hierarchy, unless a quoted price for a similar long-lived asset in an active market exists, at which time they are included in Level 2 of the fair value hierarchy.

Financial Instrument Fair Value Disclosures. As of September 30, 2021 and December 31, 2020, the carrying values of cash and cash equivalents, accounts receivable, accounts payable, accrued expenses and distributions payable represented fair value because of the short-term nature of these instruments. The carrying value of restricted cash approximates its fair value based on the nature of our assessment of the ability to recover these amounts. In calculating the fair value of our notes payable, interest rate and spread assumptions reflect current credit worthiness and market conditions available for the issuance of notes payable with similar terms and remaining maturities. These financial instruments utilize Level 2 inputs.

Income Recognition. The majority of our revenues are derived from real estate lease contracts and presented as property revenues, and include rental revenue as well as revenue from amounts received under contractual terms for other services provided to our customers. As a lessor, we have also elected practical expedients to: i) not separate the lease and non-lease components by class of underlying assets and account for the combined components as a single component under certain conditions, and ii) exclude from lease revenues the sales taxes collected from lessees and certain lessor costs paid directly by the lessee. Our other revenue streams include fee and asset management income in accordance with other revenue guidance, ASC 606, Revenues from Contracts with Customers. Details of our material revenue streams are discussed below:

Property Revenues: We earn rental revenue from operating lease contracts for the use of dedicated spaces within owned assets, which is our only underlying asset class. We recognize rental revenues from these lease contracts on a straight-line basis over the applicable lease term, net of amounts related to lease contracts identified as uncollectible. We also earn revenues from amounts received under contractual terms for other services considered non-lease components within a lease contract, primarily consisting of utility rebillings and other transactional fees. These amounts received under contractual terms for other services are charged to our residents and recognized monthly as earned. Any identified uncollectible amounts related to individual lease contracts are presented as an adjustment to property revenue. Any renewal options of real estate lease contracts are considered a new and separate contract which will be recognized at the time the option is exercised on a straight-line basis over the renewal period.

The pandemic-related concessions provided to our residents/tenants were primarily related to changes in timing of rent payments with no significant changes to the total payment or term. In accordance with the Financial Standards Board ("FASB") question and answer document issued in April 2020, we elected to account for these concessions as a deferred payment and continued to recognize property revenue on the existing straight-line basis over the remaining applicable lease term. We recognize any changes in payment through lease receivables, which is recorded in other assets, net, in our condensed consolidated balance sheets, and any identified uncollectible amounts related to deferred amounts are presented as an adjustment to property revenue.