Equity is derived based on what the market prices your property at. 

@Daniel LambertThe more units a property has the more it’s value will be derived from the income it produces.

You will divide the NOI by a Capitalization Rate (Derived from the market and sales comps you analyze).

You guys are so doom and gloom, come on man, the fed (that caused all this btw) is going to save EVERYONE, Banks, credit unions, trust and mortgage companies, investment banks, underwriters, brokerage firms, hard money lenders, stock speculators, the airline, auto, restaurant,hotel, bar, retail, casino, and travel industries,money market funds, the repo market, the global fx market, the stock market (direct purchases soon), the bond market, the derivatives market (oop's sorry ronin capital), consumer spending (helicopter money only 3 weeks away), your local bowling league and oh yea, air bnb.Don't worry the largest financial event of our lifetimes, BY FAR, will be over in a jiff and you will be rested and ready to get back to work!

Less work than Venmo since Venmo, being a Paypal derivative apparently, maintains a separate balance.

Now on derivatives, any half wit or better in the financial investment sector will ALWAYS speak to the significant risk factor and volatility to ANY derivatives investing, ANY.

For a SFR, you are  using a variety of data sources to get the comps for an area (such as market price per sqft) but with a multifamily, you are not necessarily looking at price per sqft  or "like" properties per se, rather you initially have to determine the rental price & cash flow per unit from which you can then work backwards to ascertain or derive value.Also, unless you have a property under contract, the opposite of attention is what you are typically looking for in regards any deal so you may want to learn as much about ARVs as you can -- fast!

I won’t bore you with the math to derive correlations, but I will explain a bit on how to interpret them.

Our economies, financial instruments, accounting, market manipulation, crony capitalism, derivates, currency printing and delinking from gold standard leave our economy extremely complicated and fragile compared to 1929 when things were not as complicated.

From a mortgage appraiser of 14 years,If appraised for the bank, who typically go with FNMA Guidelines, the bank will not secure the property according to a value derived through the Income Approach to value, only the Sales Comparison Approach to value.