Signs of this are poor lease quality, maybe M2M tenants, high expenses (unnecessary things like high trash bills, internet, cleaning, security).

it's a nice, expensive place to live but tougher to house hack unless you buy a big house and rent out individual rooms.)also, as @Jonathan Greene alluded to, the more you're willing to sacrifice, the better it will work. 

Californians looking to buy a house face some of the country's most expensive real estate prices and wildfires that threaten scores of housing tracts.I saw an article a day or two ago saying car insurance would/was following suit. 

For reserves, you'll want 3-6 months of potential expenses saved (repairs, vacancies, unexpected costs).

They get to save money on living expenses and we have a much higher yield then LTR's by far. 

You cannot beat the power of an ADU for peace of mind, leveraging your home to pay less monthly and reduce your expenses and give you the experience and confidence of doing constriction, getting permits and working with the city and managing a very easy rental.

Commercial appraisals are expensive, $5,000 isn't out of the ordinary.

Usually only commercial properties with established operational expenses histories are evaluated by cap rates and then those cap rates can also be applied to buildings in certain areas representing higher or lower risk areas.

He bought the property pre COVID, so his cash flow is definitely going to be different than what mine will be.The question I'm wondering if its a good idea and if the numbers make sense.Purchase Price: $100,000Down payment: $20,000 (20%)Current cashflow: $900Property manager: $90 (10%)His expense for 12 months was only $1,430 (inspections, repairs, management, eviction services). 

I use REI Hub where all my accounts are connected and I categorize income, expenses etc.