Multifamily is hot in the Bay Area with demand exceeding supply, and REITs continue to be among the companies taking advantage. So Bisnow took a few minutes to look at some of the REITs that own apartments around the Bay Area (everything from affordable to luxury) and break down the numbers for you.

1) Equity Residential

Market cap: $40.5B

Bay Area holdings: 51 properties (13,208 apartment units)

In development: 6 properties (2,045 units)

Partially owned in development: 1 properties (444 units)

(Berkeley's Gaia apartments shown above)

2) AvalonBay

Market cap: $29.7B

Bay Area holdings: 41 properties (11,974 apartment units)

In development: 2 properties (434 units)

Partially owned in development: 2 properties (505 units)

(Avalon Hayes Valley in San Francisco shown above.)

3) Essex Property Trust

Market cap: $20.3B

Bay Area holdings: 68 properties (17,604 apartment units)

In development: 2 properties (624 units)

Partially owed in development: 9 properties (2,112 units)

Note: Essex Property Trust took over BRE in 2014, growing its total national portfolio by 23,060 apartment units.

(Lakeshore Landing in San Mateo shown above.)

4) UDR

Market cap: $12.2B

Bay Area holdings: 12 properties (2,751 apartment units)

United Dominion Realty ownership in the Bay Area: 9 properties (2,185 apartment units)

In development: None in the Bay Area

Note: UDR is parent company of United Dominion Realty LP and files a combined 10K

(San Francisco's Channel Mission Bay shown above.)

5) Aimco

Market Cap: $10.4B

Bay Area holdings: 11 properties (2,169 apartment units)

In development: 1 property (126 units)

Note: Aimco divested 8,127 units from its nationwide portfolio in 2014.

(Monterey Grove in San Jose shown above.)

Information on the REIT rankings and market cap comes from 2015 NMHC 50 report. Holdings and development information comes from annual SEC filings ending December 2014.