Areas are identified as A, B, C and D.A = Very desirable, high valued properties, low crime, great rated schools.  

High cap rates are rare, but they do happen.

Property Condition & Amenities: it’s important to, “Maintain to the Neighborhood.”Key metrics for each Property Class:Class A Properties:Tenant Pool: Majority of FICO scores 680+, no convictions/evictions in last 7 years.Tenant Default: 0-5% probability of eviction or early lease termination.Section 8: Class A rents are too high and won’t be approved.Vacancies: 5-10%, depending on market conditions.Cashflow vs Appreciation: Typically, 3-5 years for positive cashflow, but you get highest relative rent & value appreciation.Class B Properties:Tenant Pool: Majority of FICO scores 620-680, some blemishes, no convictions/evictions in last 5 years.Tenant Default: 5-10% probability of eviction or early lease termination.Vacancies: 10-15%, depending on market conditions.Cashflow vs Appreciation: Typically, 1-3 years for positive cashflow, balanced amounts of relative rent & value appreciation.Section 8: Class B rents are usually too high for the Section 8 program.Class C Properties:Tenant Pool: Majority of FICO scores 560-620, many blemishes, but should have no convictions/evictions in last 3 years.

HVAC could be that high, but that is a big number and I would plan on replacing 8-10 years, not 17. 17 can definatley happen, but likely wont' last near that long.

In virtually all markets, the high LTV loan on the refinance at market terms will create an initial monthly negative cash flow when properly allocating for vacancy and sustained expenses for traditional LTR.  

So high probability that the ADU will be a value subtract meaning addd less value than the cost. 

It can get more passive as you move up the food chain, but it's always work, just different work. 

In the meantime: bag and wash/dry all fabrics on high heat, reduce clutter, vacuum thoroughly (and dispose of the bag immediately), and avoid moving items out of the house so they don’t spread.

The place is in a high wildfire risk zone so insurance is sketchy, maybe has something to do with lending restrictions.

Rents are high so a roommate would end up paying a significant portion of the mortgage.