Calabasas, Cal., Code of Ordinances ch. 17.22 § 17.22.040

The location of affordable units within the qualifying project shall be at the discretion of the city with the goal to integrate the units into the overall project. The city has determined that, to the extent feasible, projects that provide housing units for very low, low and moderate income households should be designed to locate the units as follows: A.
The number of assisted housing units in any project, except for those designed for the elderly or disabled, should not exceed forty (40) percent of the total number of units in the project;
B. Assisted housing should be located within reasonable proximity to public facilities, including convenient shopping, public schools, park and recreation facilities, transportation services, and employment centers; and
C. Assisted units, except those for the elderly, should be distributed throughout the project site, and not grouped together in a single area.
D. To the extent that subsections (A) through (C) are not feasible, or circumstances arise in which the public interest would be served by allowing some or all of the affordable units associated with one housing development to be produced and operated at an alternative development site, such a site may be utilized. Under these circumstances, the resulting linked developments shall be considered a single housing development for purposes of this chapter, and the permit applicant shall be subject to the same requirements of this chapter for the affordable units to be provided on the alternative site. Where the director determines that on-site provision of affordable housing is not feasible, the review authority may approve one or more of the alternatives listed below (or other alternatives determined by the review authority to be equally effective). Any approved alternatives shall be carried out under a development agreement ( Chapter 17.68 ) between the applicant and the city for covering the entire project.
1. New Construction of Affordable Housing. An applicant may construct a number of new affordable units off-site equal to the number that would otherwise have been required on-site.
2. New Construction of Special Needs Housing. An applicant may construct new units off-site that are specifically designed to meet the needs of an identified special needs population. This housing may include emergency shelters, special care homes, employee housing, senior housing and hospices. Each unit created under this alternative shall satisfy the requirement for two affordable units as required by subsection (A)(1) of this section.
3. Conversion of Market Rate Housing. An applicant may convert market rate housing to affordable housing through a "buy down" mechanism, and establishing restrictive covenants or similar protection of the affordability of the converted units.
4. Rehabilitation of Existing Housing Stock. An applicant may rehabilitate structures that currently do not comply with Title 15 of this Code, and have been deemed uninhabitable by the city. Housing appropriate for rehabilitation need not be price restricted, and must be determined by the review authority to be affordable based on its age and/or condition.
5. Preservation of Existing Affordable Housing. An applicant may extend the lifetime of an existing restrictive covenant on affordable units that have been identified by the city as being "at risk" of conversion to market rate housing within a five-year period.
6. Payment of In-Lieu Fee. An applicant may pay an in-lieu fee as set by council resolution. The fee shall be deposited in a designated fund to be used for the preservation and development of affordable housing.
7. Timing of Fee Payment. Where a fee is required, the fee shall be paid prior to issuance of building permits.
E. Commercial Projects. A commercial, office or manufacturing/industrial development that introduces new workers into the community and thereby creates a need for more new housing than is available within a five-mile radius of the site, shall either, as determined to be appropriate by the director:
1. Design the development as a mixed-use project, providing housing affordable to employees within the project site; or
2. Pay to the city the housing impact fee established by the council, which will be placed into a housing trust fund administered as provided by the General Plan and council resolution.