On September 8, 2020, we formed a joint venture with a passive institutional investor to own a portfolio of 12 multi-family apartment communities with 4,051 homes located in California. The communities included in the joint venture were valued at $2.4 billion, or approximately $592,000 per apartment home. The joint venture has existing property debt of $1.22 billion and an implied equity value of $1.18 billion. In exchange for a 39% equity interest, we received $461 million. We retain ownership of 61% of the joint venture and will control and operate the communities in exchange for property and asset management fees. We evaluated the joint venture and concluded that we will continue to consolidate these communities. The difference between the consideration received and the carrying value of the interest sold was recognized in additional paid-in capital.

On August 25, 2020, we acquired Hamilton on the Bay for $89.6 million. The assets and liabilities of Hamilton on the Bay were retained by Aimco concurrent with the Separation and are not included on our consolidated balance sheets as of December 31, 2020.

Sold apartment communities during the years ended December 31, 2020, 2019, and 2018, are summarized below (dollars in thousands):

	2020		2019		2018
Number of apartment communities sold		2		12		4
Number of apartment homes sold		485		3,596		1,334
Gain on dispositions of real estate (1)	$	119,215	$	503,168	$	175,213

The apartment communities sold were predominantly located outside of our primary markets or in lower-rated locations within primary markets and had average revenues per apartment home significantly below those of our retained portfolio.

During the year ended December 31, 2018, we also sold for $590.0 million our Asset Management business and our four affordable apartment communities located in the Hunters Point area of San Francisco. The sale resulted in a gain of $500.3 million and net cash proceeds of $512.2 million, after payment of transaction costs and repayment of property-level debt. Additionally, we sold our interest in the entities owning the La Jolla Cove property. We provided seller financing with a stated value of $48.6 million and received net cash proceeds of approximately $5.0 million during the year ended December 31, 2020. The net amount of seller financing associated with this transaction was retained by Aimco in the Separation.

In addition to the apartment communities we sold during the current period, from time to time we may be marketing for sale certain communities that are inconsistent with our long-term investment strategy. At the end of each reporting period we evaluate whether such communities meet the criteria to be classified as held for sale. As of December 31, 2020, no communities were classified as held for sale.