Again, I believe this would hold true in most urban type markets.Let me know if that helps answer your question or if you have any follow-up questions to this.

Prove that up to the seller so that they know you are a great credit risk. 

I know enough about a lot of things to be dangerous, but lack detailed expertise and certifications.I will say that I was extremely disappointed with my last realtors lack of construction knowledge so you will have a leg up there for sure, and you should play up that as a selling point

Quote from @Catherine Ashmead: Does anyone know of good companies in Arizona that I can contact?

Yep I know it- I've had multiple tax clients over the years face a mean surprise with that. 

Or just sell it at a loss… I need some guidance here, I know very little about real estate investing other than I know I’ll be losing money after maintenance and paying a property manager.

How does he know what we are doing the house?

But, assuming this is a fairly accurate number, the little I know about San Diego (and quick look on Zillow for multifamily properties) seems like $1.5mm is the minimum asking price for two units.  

I don't know how much you have but a build to rent triplex all in our market is 150k liquid normally with full return of capital in 9 months.

2. how to know where to find a B,C,D areas\neighborhoods in cities\ countries.3. how do I know if a property is worth the checking\ buying?