At a minimum,  you should understand what the current zoning is and what restrictions there are.As the post above mentioned reaching out or going in person to speak with the planning and zoning department will be very helpful. 

This is something I have been trying to understand. 

These methods include: Detailed Engineering Cost ApproachDetailed Engineering Cost Estimate ApproachSurvey or Letter ApproachResidual Estimation ApproachSampling or Modeling ApproachExperience or “Rule of Thumb” ApproachIt’s important to understand the differences between the approaches including which one best fits your property and the reliability of each approach.DETAILED ENGINEERING COST APPROACHThis approach compiles the costs from construction and accounting reports to build a report.

Its my understanding that SF has pretty tight Air BNB restrictions like you have to register and can only rent them a certain number of days a year?

If you don't have an agent...well...nothing is a problem until it's a problem but our advice and opinions are meaningless if you actually need to use your insurance.It's vitally important that you understand exactly what you have before you need it. 

they said around 90% of market value.I tried to get them to understand that this property needs a LOT of work, almost a full gut, some holes in walls (small) old carpet needs to be ripped up, i mean like the works on this thing, you can prob get away with touching up the kitchen since its real hardwood and the bathrooms as well but this prop needs at least 80k.Found out owner actually owes 140k on property, and zillow is zestimating it to be 127k.

@Frederic BabeuxOn citrus anywhere in the world, make sure you understand "Greening".Same thought on Coconuts, understand "Yellowing".Anyone on Belize, don't invest there unless you have made many trips there and either have an onsite Caretaker or a gated Condo community.

I understand that rents will go up over time and my mortgage payment will pay down the principal, but it seems like investing the $1.43mil into rental properties and/or a low fee US stock market fund may work out better for me. 

However, help me understand.

I understand that most "Dips" don't last that long when you zoom out, as long as I can withstand the storm when it does come, then i'm good.