Capitalization rate and Net initial yield are similar but not the same concept although they are frequently used interchangeably by brokers.
Capitalization rates imply that the property is let at market rentals into perpetuity and used to compare similar investment properties. Net yields are simply the first year’s income less expenses divided by the purchase price expressed as a percentage. This is the same basic formula usde in determining a Capitalization or “Cap” rate but the essential difference is the rental is the actual net rental and may be above and below the market rental.
More advanced methods of valuation use discounted cash flow and net present value comparisons.