So I'm late to, but here are some thoughts that haven’t been covered yet– there’s potential for a couple of strategies if you are willing to owner occupy (at least for a while) and expect to stay put for a time. My wife and I are in the Sacramento area and buying a new construction home that has a JADU already as part of the plan. These are actually the new BIG thing in new construction. Check out this link to a floorplan by Lennar, one of the country's biggest builders.
https://www.lennar.com/new-hom...
People are drawn to the flexibility of JADU floor-plans as they can use the space for all sorts of things: home office suite; room for an older teen; adult child living at home; In-Law unit; Airbnb; home gym; rental... You get the idea.
So investing. For a rental, there are lots of advantages to ADUs, and doing both a Jr and a detached let you double up. Pay property taxes for one property instead of three, same with city services, and lots of other things too.
Yes, if you rent a JADU, you’ll have to owner occupy. At least for a time. But if you want to make the most out of your residence as an investment, building both units is a great way to do it. When you want to move, you have two choices:
1) Sell. As stated above, homes with JADU plans are very popular and increase the value, probably more than an ADU in that there are lots of threads with folks having trouble getting the assessment to properly value the ADU. A JADU can be treated as just another wing of the house and included in square footage, etc.
2) Keep renting! You can always rent the main residence and the JADU together and also rent the ADU. Sure, it won't bring in as much as if you could rent all three, but it leaves you options.
As for OO requirement, it does have some upsides and ways to off-set the down. OO means you can easily manage the property yourself. You can keep an eye on things just by doing your normal routines. Also, you're likely to get better tenants as they know that having you there means they won't be able to throw frat parties every other day. As for privacy, with the right property, you can easily put up fences, hedges, etc that make each unit more like any other neighbor than a roommate. I definitely wouldn't be trying my hand at this otherwise!