Also how much for an accessory dwelling and ask your realtor how much value it would add to the house. 

Much of the staging impact is achieved with accessories.  

No idea if it is accurate or if anything has changed since then, but it indicated the following:PROGRAM 1 Owner use up to 2 weeks 50% of Adjusted Gross Standard FF&E in high season & 2 weeks Revenues from the Unit and accessory in low season package required.

I am looking into them as accessory dwelling units(ADU)

I wouldn’t necessarily give up on your idea to add an accessory dwelling unit to your property.  

Some other supposedly housing-related bills that will end the housing crisis, signed into law by Governor Nuisance:AB 12 by Matt Haney (D-San Francisco) – Tenancy: security deposits.AB 84 by Christopher Ward (D-San Diego) – Property tax: welfare exemption: affordable housing.AB 281 by Tim Grayson (D-Contra Costa) – Planning and zoning: housing: post entitlement phase permits.AB 318 by Dawn Addis (D-Morro Bay) – Mobilehome Residency Law Protection Act.AB 319 by Damon Connolly (D-San Rafael) – Mobilehome Parks Act: inspectors: conflict of interest: enforcement actions: sunset.AB 323 by Chris Holden (D-Pasadena) – Density Bonus Law: purchase of density bonus units by nonprofit housing organizations: civil actions.AB 346 by Assemlymember Sharon Quirk-Silva (D-Fullerton) – Income tax credits: low-income housing: California Debt Limit Allocation Committee rulemaking.AB 434 by Tim Grayson (D-Contra Costa) – Housing element: notice of violation.AB 480 by Philip Ting (D-San Francisco) – Surplus land.AB 516 by James Ramos (D-San Bernardino) – Mitigation Fee Act: fees for improvements: reports and audits.AB 519 by Pilar Schiavo (D-Los Angeles) – Affordable Housing Finance Workgroup: affordable housing: consolidated application and coordinated review process.AB 529 by Jesse Gabriel (D-Encino)- Adaptive reuse projects.AB 548 by  Tasha Boerner (D-San Diego) – State Housing Law: inspection.AB 572 by Matt Haney (D-San Francisco) – Common interest developments: imposition of assessments.AB 671 by Christopher Ward (D-San Diego) – CalHome Program: accessory dwelling units.AB 812 by Tasha Boerner (D-San Diego) – Housing development approvals: reserving affordable units in or near a cultural district for artists.AB 821 by Tim Grayson (D-Contra Costa) – Planning and zoning: general plan: zoning ordinance: conflicts.AB 894 by Laura Friedman (D-Los Angeles) – Parking requirements: shared parking.AB 911 by Pilar Schiavo (D-Los Angeles) – Unlawfully restrictive covenants: affordable housing.AB 976 by Philip Ting (D-San Francisco) – Accessory dwelling units: owner-occupancy requirements.AB 1033 by Philip Ting (D-San Francisco) – Accessory dwelling units: local ordinances: separate sale or conveyance.AB 1114 by Matt Haney (D-San Francisco) – Planning and zoning: housing development projects: post entitlement phase permits.AB 1218 by Josh Lowenthal (D-Los Angeles) – Development projects: demolition of residential dwelling units.AB 1287 by David Alvarez (D-San Diego) – Density Bonus Law: maximum allowable residential density: additional density bonus and incentives or concessions.AB 1308 by Sharon Quirk-Silva (D-Fullerton)- Planning and Zoning Law: single-family residences: parking requirements.AB 1317 by Wendy Carrillo (D-Los Angeles) – Unbundled parking.AB 1319 by Buffy Wicks (D-Oakland) – Bay Area Housing Finance Authority: housing revenue.AB 1332 by Juan Carrillo (D-Palmdale) – Accessory dwelling units: pre-approved plans.AB 1386 by Jesse Gabriel (D-Encino) – Veterans housing: tenant referrals.AB 1449 by David Alvarez (D-San Diego) – Affordable housing: California Environmental Quality Act: exemption.AB 1474 by Eloise Gómez Reyes (D-San Bernardino) – California Statewide Housing Plan.AB 1485 by Matt Haney (D-San Francisco) – Housing element: enforcement: Attorney General.AB 1490 by Alex Lee (D-San Jose) – Affordable housing development projects: adaptive reuse.AB 1508 by James Ramos (D-San Bernardino) – Department of Housing and Community Development: California Statewide Housing Plan.AB 1528 by Mike Gipson (D-Los Angeles) – Housing authorities: property taxation.AB 1620 by Rick Chavez Zbur (D-Los Angeles) – Costa-Hawkins Rental Housing Act: permanent disabilities: comparable or smaller units.AB 1633 by Philip Ting (D-San Francisco) – Housing Accountability Act: disapprovals: California Environmental Quality Act.AB 1734 by Reginald Byron Jones-Sawyer Sr.

This means you can rent out a room in your place while you also stay there, you can rent out you entire place while on vacation, or you can rent out a basement or attic unit or an accessory dwelling unit (carriage house).

I understand a duplex may have an Accessory Dwelling Unit (ADU).The objective is to get a permit to change the windows, put up siding, and add a fence.  

I don't allow tenants to smoke any substance, or vape, inside their units, garages, or outbuildings.

Researched uncovered that Accessory Dwelling Unit (ADUs) are allowed in R2.. yet seems to require a $4000 statement of occupancy.