This house was laid out as two separate units, upstairs and downstairs. Rick, the prior owner, explained that periodically he did have tenants. A couple of nice Danes at one point and a New Zealand couple that were heavily in to boating at another point. Tenants made his life interesting. 

Since the second unit existed, the concept of having a tenant seemed like a no brainer. Terry was OK with it, since we had enough space, and the income would help offset the expenses associated with fixing-up the property. 

I contacted the county. They explained that, if I could convince them that the unit was built before 1986 (easy, since it definitely looks 40 years old!) then I would have a few less hurdles to overcome, to legalize it. Apparently the main advantage of the unit being "pre-existing" is that I would be required to have only three independently accessible (vs. one behind the other) parking spots, as opposed to perhaps twice that many.

At street side, we had a cutout in the hillside, supported by a few rows of cinder blocks, plus stacked railroad ties. It was about one and a half cars wide, so three cars didn't sound that tough to pull off. Boy was I ignorant.

The first thing required was a survey, to officially identify what belonged to the street, and what belonged to me. Surveys are expensive. But I proceeded, hiring Larry Doyle. What I learned was that the street was a yard wider than the eye suggested, and thus I would need to dig a yard deeper into the hill, in order to have a legally-sized spaces. Oh - and the spaces required per card was 18.5' by 8.5' wide. That's massive. I was learning to appreciate the irony of living in a community that aggressively advocated affordable housing, yet made the creation of that housing unaffordable. 

During the county's official second unit inspection, I was advised that, in addition to the additional parking, I had to remove a step, add a smoke detector, add another dedicated outlet in the kitchenette, and add a dedicated source of heat for the downstairs bedroom. Permits were pulled for these and the changes were made.

Fees

Although the county periodically promotes amnesties and discounts on their permit fees associated with second-unit legalization, be warned: other entities will get their fingers into your wallet. As my paperwork was being completed, the county advised me that I would need to get approval from three local entities: Southern Marin Fire Protection District, Almonte Sanitary District, and Marin Municipal Water District. I was warned that it wouldn't be cheap.

Southern Marin Fire Protection District was a breeze. The inspector came out, looked for the basics (smoke detectors and fire extinguishers) and told me that everything would be fine.

Almonte Sanitary District didn't bother visiting. They just informed me that their approval would require a payment of $1,600. Needless to say, this seemed like larceny. The unit had been here for decades, but their approval required a 4-digit check. I begrudgingly coughed-up the money.

Marin Municipal Water District also didn't bother visiting. They demanded a payment of $2,300. I decided not to pay immediately, since the foundation remodel meant that the unit would not be available for months. I phoned back a month or so later, and learned that IF I COULD PROVE that the unit existed prior to 1987, there would be no fee. On the one hand, I was annoyed that I was not told this the first time. On the other hand, I was thrilled to have the chance to save $2,300.

MMWD did not make it easy, but truth was on my side. After submitting a notarized letter from the prior owner, date-stamped 30-year-old photos, etc, they gave the County their approval - without getting $2,300 from me.