A casita is a little house on your lot. In California it is a detached ADU.

In California, a casita you can live in is an ADU — almost always a detached one. Government Code §66313 defines an accessory dwelling unit as a residential dwelling unit that “provides complete independent living facilities,” with “permanent provisions for living, sleeping, eating, cooking, and sanitation.” Avorino publishes the same equivalence: an accessory dwelling unit is also called a granny flat, casita or backyard cottage. A guest room or pool house with no kitchen is an accessory structure, not an ADU.

A casita is built and permitted as a detached ADU, and Avorino publishes that type at typically $245K – $440K+ for 500 – 1,200 sqft. What the band covers: New foundation, full kitchen + bath, independent utilities. Where a project lands inside it comes down to size, stories, utility runs, finish level and site access. The Avorino ADU cost estimator prices your own city, square footage and finish level in about a minute.

Within the state bracket: §66314(d)(5) caps a detached unit at 1,200 square feet of floor area, and §66321(b)(2) bars a city from capping one below 850 square feet of interior livable space, or below 1,000 square feet where the unit has more than one bedroom. Avorino builds detached units at 500 – 1,200 sqft, Studio – 3 BR; the full state standard set is on the detached ADU page.

Construction on a detached unit typically runs 5–8+ mo, with design, engineering and the city's 60-day review of a completed application (§66317(a)(3)) ahead of it; we do not publish a single end-to-end number, and the permit mechanics are on the detached ADU page.

Yes — a casita is permitted as a dwelling, not as an accessory building. Government Code §66317(a)(1) says an ADU application “shall be considered and approved ministerially without discretionary review or a hearing,” so there is no design board and no neighbor vote. §66317(a)(3) gives the city 60 days from a completed application, after which it “shall be deemed approved.” The clock starts at completeness, not at first submission, which is why we carry the comments and the resubmittal.

Government Code §66315 bars any standard beyond those in §66314, “including an owner-occupant requirement, except that a local agency may require that the property may be used for rentals of terms 30 days or longer.” So a city cannot make you live on the property, and it can require rentals of 30 days or longer rather than by the night. Run the rent and payback numbers on the Avorino ROI calculator.

Yes — Avorino has built one, the 1,000 Sq Ft Two-Story ADU in Santa Ana Hills. Whether yours can depends on the lot: Government Code §66321(b)(4) bars a city from setting a height limit below 16 feet for a detached unit, or below 18 feet near a major transit stop or on a lot with a “multifamily, multistory dwelling,” and those are floors, not ceilings; the full standard set is on the detached ADU page.