So I'm looking for a way to lower my housing costs with this plan.The plan is to build an Accessory Dwelling Unit (ADU) in my basement, essentially turning my home into a duplex.

Within the city limits (I think both suburban and urban tiers) you can now have, by right, up to 3 units (2 in the form of a duplex and 1 in the form of a detached accessory dwelling unit).Of course, the problem is that construction costs are so high, ADUs are difficult, but if you have a garage that could be converted easily, that could be a good way to go!

What I beleive you want to research regarding the detached carriage house is a dwelling called an "Accessory Dwelling Unit" (ADU). 

You may also be able to find a home that has an accessory dwelling unit as well, if you are going to be living there.

Right now appraisers are having a problem with the accessory dwelling units.

Is this going to be converted to a rental as an accessory unit or into a two dwelling flat (the zone will determine which one you can do)?

@Vincent LudegnaAn ADU is an acronym for an “accessory dwelling unit”.

Therefore a two or three bedroom property cannot rent more than one bedroom at a time.The rental portion of the residence must be designated as an accessory use space.Must include the registration number in all advertisements.

Hi @Sam Leon I've looked at quite a few properties with Mother in laws/accessory suite/Accessory dwelling unit whatever you want to call it.

I am trying to add an accessory dwelling unit in San Francisco to a pre-rent control building and the city is requiring me to opt out of my Costa Hawkins rights in order to receive permission to build that extra unit.