@Julie Garner This contractor texted me after I received the quote to let me know that materials are included.

UPS box is more expensive, but can do more things such as used as a business entity's main address on record.

This is not including any financing costs and closing cost which can easily bump that number to 23k. 

We’re moving into the ADU ourselves starting in January so we can remodel our main home.

Lots of folks come up from Ventura County, including many who responded to your post. 

if you are going to do things like include utilities, or have an off street parking spot, other amenities etc, there's no reason in my mind you couldn't "charge a premium" for a premium unit/service. 

@Kevin Wood: Fixed Asset Management module is included in the QuickBooks Accountant version where you can calculate the depreciation.

Quote from @Harrison Jones: Quote from @JD Martin: OK, so after reading your post, my main and only thought was:Why?

Does that include utility service to the house, a driveway, septic and well? 

I've included an example below to help illustrate this.So different lenders have different rates (which do vary even for DSCR loans) but these are factors they all consider.See example below:DSCR < 1Principal + Interest = $1,700Taxes = $350, Insurance = $100, Association Dues = $50Total PITIA = $2200Rent = $2000DSCR = Rent/PITIA = 2000/2200 = 0.91Since the DSCR is 0.91, we know the expenses are greater than the income of the property.DSCR >1Principal + Interest = $1,500Taxes = $250, Insurance = $100, Association Dues = $25Total PITIA = $1875 Rent = $2300DSCR = Rent/PITIA = 2300/1875 = 1.23If a purchase, you also generally need reserves / savings to show you have 3-6 month payments of PITIA (principal / interest (mortgage payment), property taxes and insurance and HOA (if applicable).